organic chemistry for cosmetic chemists tony o’lenick thomas o’lenick, phd october 2015
TRANSCRIPT
Organic Chemistry
Organic Chemistry however has profound effects upon our formulations. This becomes clear when a formulator tries to
substitute one raw material for another. Armed with only INCI names this can be a best a
frustration or at worst a complete failure.
Why is this the case?
Organic Chemistry
Why is this the case?1. Many of our raw materials come from different raw
material bases and despite common names are not identical.
2. Many manufacturers use different processes to make their products.
3. These differing processes result in different % conversion, by products and un-reacted raw materials.
4. Many manufacturers use processing aides, and other additives.
Back the the Basics
Before we dive into Organic chemistry or more commonly called O-Chem we need the basics
First off
Back the the Basics
How do we draw Chemical Structures
Hydrocarbons- All Carbon and Hydrogens Alkanes Alkenes Alkynes Cyclic
Aromatic Compounds
CH3CH2CH3
Hydrocarbon
Hydrocarbons are organic compounds that are composed of carbon and hydrogen.
To start the naming process we need to start with the simplest form. Compounds with all single Carbon-Carbon bonds.
Hydrocarbons are named by identification of the longest continuous carbon chain.
They are named by the number of carbons in that chain followed the suffix “-ane”
Hydrocarbons
Now come the memorization part…
The prefixes…
Number of
Carbons
Name Molecular
Formula
Structural Formula
1 Methane CH4 -
2 Ethane C2H6 CH3CH3
3 Propane C3H8 CH3CH2CH3
4 Butane C4H10 CH3(CH2)2CH3
5 Pentane C5H12 CH3(CH2)3CH3
6 Hexane C6H14 CH3(CH2)4CH3
7 Heptane C7H16 CH3(CH2)5CH3
8 Octane C8H18 CH3(CH2)6CH3
9 Nonane C9H20 CH3(CH2)7CH3
10 Decane C10H22 CH3(CH2)8CH3
Isomers
What are isomers? When you have two or more chemical structures
that have the same molecular formula but different structures.
Example How many Isomers of pentane (C5H12) can you draw?
1Pentane
22-Methyl Butane
32,2-Dimethyl Propane
Branching?
When a carbon chain is handing off of the carbon chain but is not part of the primary carbon chain, you name the number of carbons, but add a –yl at the end.
Heptane3-Methyl Heptane
4-Ethyl 3-Methyl Heptane
3-Methyl 4-Propyl Octane
What about?
Cyclic Alkanes
1
2
3
45
C5H10
PentaneCycloPentane
No it is not an isomer. It has 2 fewer hydrogens.
Cyclic compounds have the same type naming but the word Cyclo-
Hydrocarbons
Number of
Carbons
Name Molecular
Formula
Structural Formula
2 Ethene C2H4 CH2=CH2
3 Propene C3H6 CH3CH=CH2
Alkenes are: Compounds with at least one Carbon-Carbon double
bond.
Name them the same way you name alkanes, except:1. You have to identify where the double bond is
2. Drop the –ane and replace it with –ene.
Alkynes
Number of
Carbons
Name Molecular
Formula
Structural Formula
2 Ethyne C2H2 CHCH
3 Propyne C3H6 CH3CCH
Alkynes are: Compounds with at least one Carbon-Carbon triple
bond.
Name them the same way you name alkanes, except:1. You have to identify where the double bond is
2. Drop the –ane and replace it with –yne.
Conjugation
Conjugation as we have seen, leads to stability and if the conditions are correct, aromatic compounds.
There is another added benefit that we see a lot in cosmetic chemistry….Absorption
Before we discuss how conjugation, lets briefly discuss absorption in organic molecules.
Resonance
Lets review Alkenes
Now we have a diene.
When dienes are on adjacent carbons, they can have resonance with each other.
+
−
Aromatic Compounds
Aromatic Compounds, also known as arenes or aromatics, are chemical compounds that contain conjugated planar ring systems with delocalized π electron clouds instead of discrete alternating single and double bonds. Typical aromatic compounds are benzene and toluene. They should satisfy Hückel’s rule.1
So….what does that really mean?
1. http://en.wikipedia.org/wiki/Category:Aromatic_compounds
Aromatic Compounds
http://www.sparknotes.com/chemistry/organic1/covalentbonding/section2.rhtmlhttp://en.wikipedia.org/wiki/August_Kekulé
http://en.wikipedia.org/wiki/Ouroboros
Absorption of Organic Molecules
Absorption can provide information about organic materials.
There are 2 important absorptions Infrared UV-Vis
Infrared Tells us what kind of bonds
are involved.http://ajwin.us/uvbnarrowband.com/index.php/the-blog/
Conjugation’s effect on Absorption
UV light has just the right amount of energy to cause an electronic transition.
It is the energy gap that determines what wavelength is absorbed.
Alcohol
Alcohols are named by the functional hydoxyl group. - OH
Alcohols can be branched or linear. Oxygen prefers to have 2 bonds, so they are classified
according to what they are connected to.
Amines
Amines are named based on this functional group. -NHx
Nitrogen likes to make 3 bonds They are named based on how many non-hydrogen
atoms are bonded to the Nitrogen.
CH3NH2
Primary Amine
CH3NH CH3
Secondary Amine
CH3N CH3
Tertiary Amine
CH3
H
+
Ethers
Ethers are named based on this functional group.R1-O-R2
Oxygen likes to have 2 bonds, so ethers are typically non-reactive They are named by their alkyl chains.
CH3O CH3
Dimethyl ether
CH3O CH2CH3
Methyl Ethyl ether
Carbonyl Group
There is a large subsection of functional groups that are based on the Carbonyl group.
The carbonyl groups is R2C=O
The functional group is then based on what R is.
The Carbon in the Carbonyl is reactive and is very important in Organic synthesis.
Aldehyde
Aldehyde is conforms to the following structure.
They are named by their parent alkyl chain, but drop the –e and replace it with –al.
O
H
O
HHMethanal
(Formaldehyde)
O
HCH3
Ethanal
Ketones
A ketone where the R group(s) are carbons.
They are named by their parent alkyl chain, but drop the –e and replace it with –one.
O
R1
O
CH3H3CDimethyl Keytone
(Acetone)
O
CH2CH3CH3CH2CH2
3-Hexanone
R2
Carboxylic Acid
An Acid is a carboxyl with a C(O)OH.
They are named by their parent alkyl chain, but drop the –e and replace it with –ic acid
O
OH
O
OHH3CEthanoic Acid(Acetic Acid)
O
OHCH3CH2CH2
Hexonic acid
R2
Esters
An Ester is a carboxyl with a C(O)OR.
They are named by their parent alkyl chain with the carbonyl, but drop the –e and replace it with –oate
O
OR1
O
OCH3H3CMethyl Ethanoate(Methyl Acetate)
O
OCH2CH3CH3CH2CH2
Butanoate
R2
Ethyl
Anhydrides
Anhydrides are compounds that have the following structure.
They are named by their parent alkyl chain with the carbonyl, but drop the –e and replace it with –oic anhydride
O
O
O
OH3C
Ethanoic Anhydride
O
CH3CH2CH2
R2
O
R1
O
CH3 O
O
CH2CH3
Butanoic Propanoic anhydride
Epoxides, Alkyl Halides and Acyl Halides
Epoxides (oxarines) are 3 membered rings. O
H2C CH2
Alkyl HalidesCH3CH2-X X = Cl, Br, F, ect.
Acyl HalidesO
XR2
X = Cl, Br, F, ect.
Some Synthesis Concepts
Umpolung Is a rather obscure German word, it means “Group
Reversal”.
One of the most dramatic uses of this concept can be seen in the making of esters. Lets do an example…. Lets Draw
Stearyl Oleate & Oleyl Stearate
Umpolung
Sometimes1. Lack of availability of technical data;
2. Multiple methods of naming;
3. Different raw materials
Cause confusion in using this concept
Analogues and Homologues
A very important concept that one needs to understand the difference between an analogous series and a homologous series
Analogous series are those that differ only in the functional group present.
So, for example, sodium laureth-2-sulfate and sodium laureth-2-phosphate are two analogues.
Their common raw material is lauryl alcohol with two moles of ethylene oxide.
Analogues
The substantial difference in properties between these analogues is due only to the different functional groups.
Changes within a analogous series generally result in profound differences, including compatibility with other ingredients.
Homologues
If one varies the carbon chain in the group, a series of homologues is prepared.
Such a homologous pair is sodium lauryl (C12) sulfate and sodium behenyl (C22) sulfate.
The differences in the properties of these two surfactants are due to the differing number of carbon atoms in the molecule.
Changes within a homologous series generally result in different melt points, foam, viscosity and conditioning effects
It is often advantageous to take into account such differences as these in order to select a chemistry that will give the desired property. The process becomes even more complicated when one considers modifications that change both functionality and carbon chain distribution.
Raw Materials
There are many different “chemicals” out there to make products from. Several components go into picking the correct
starting materials. Cost Availability Purity
Origins of Materials
Natural Oils(Triglycerides)
Petroleum(Crude Oil)
Minerals(Quatz)
Methyl Esters Ethylene Propylene
Silicon
Fatty Alcohols Alpha Olefins Chlorosilanes
Fatty Amines Fatty Alcohols Silicone
Glycerin Fatty Amines Organofunctional
Natural Oils Triglycerides Petroleum-based
Alcohol
Alkanolamide
Phosphate
Sulfate
Sulfosuccinate
Ethoxylates
Ether Sulfate
Ether Phosphate
EtherSulfosuccina
te
Ether Carboylate
Ether Ester
Guerbet Alcohols
Esters
Sulfates
Phosphates
AcidsMethyl Ester
Alkanes,Alkenes &Alkynes
Natural Oils Triglycerides Petroleum-based
Alcohol
Alkanolamide
AcidsMethyl Ester
Alkanes,Alkenes &Alkynes
Alkanolamide
Ethoxylated Amines
AminosulfosuccanateImidazoline
Amphoterics
Sulfobetaine
Phophobetane Fatty Amine
Betaines
Quats
Amphoteric
Betaines
Triglycerides
Triglycerides are key raw materials
Triglycerides are the fatty tri-ester of glycerin.
OO
O
O
R
O
R1
O
R2
Triglyceride
Typically there are 3 classes of Triglycerides
Why is this important?
Class I Products Rich in Components below C18
Class II Products Rich in Unsaturated Components
Class III
Products Rich in Components with Chain Lengths Higher than C18
Coconut Oil
Source: Coconut oil is the most abundant
processed natural oil. Comes from the seeds of the cocs
nucifera plant. Is the major source of Lauric Acid
(C12)
Component
Concentration
(% wt)
C8 8.0
C10 7.0
C12 48.0
C14 19.0
C16 8.0
C18 3.0
C18:1 5.0
C18:2 2.0
Soybean Oil
Source: Comes from the soybean glycerin
max.
Component
Concentration
(% wt)
C8 -
C10 -
C12 -
C14 -
C16 7.0
C18 4.0
C18:1 29.0
C18:2 54.0
C18:3 5.0
Meadowfoam Oil
Source: Derived from the herbaceous winter
plant (limnanthes alba).
Component Concentration
(% wt)
C20:1 (n = 5) 63.0
C20:2 (n = 5.13)
12.0
C22:1 (n = 5) 3.0
C22.1 (n = 13)
12.0
C22.2 (n = 5.13)
10.0
Carbon-Carbon Bonds?
Double bonds or unsaturation tends to: Turn dark when heated Go rancid over time
Methyl Esters
Methyl esters are made by the reaction of a triglyceride with methanol in the presence of a catalyst.
Commercial manufacturing of methyl esters is accomplished by using a continuous hydrogenolysis process.
The Methyl ester is separated from the glycerin and distilled to produce narrow fraction products useful as ram materials for the preparation of surfactant products.
OO
O
O
R
O
R1
O
R2 + 3 CH3OH
OHHO
OH
O
R2 OCH33 x
Organic Chemistry
There are many reactions involved in organic chemistry….
Instead of memorizing name reaction after name reaction, it is much simpler to breakdown the reactions into simple steps or trends.
With the understanding of these trends, we can understand the reaction without memorizing a bunch of reactions.
Reactions
Rule number 1 when we start looking at reactions is ALWAYS PUSH ELECTRONS!!!
Reactions always go from atoms with high electron content to electron deficient atoms.
The atoms with high electron content are called Nucleophilies.
Electron deficient atoms are called electophiles
Typical Nucleophilies
Lone Pair Electrons: O , N, S, Cl, Br, I
π-bonds
http://www.masterorganicchemistry.com/2011/03/04/the-three-classes-of-nucleophiles/
What is a “Subsitution Reaction”?
Simply put a Subsitution reaction is replacing one group with another, or subsituting one group for another.
There are 2 basic Subsitution reactions:1. SN1
2. SN2
Can be used to make Amids, Esters, Quats, ECT..
Subsitution Reactions
Neclophillic Subsitution Reaction
SN1 SN1 Reactions are a two step reaction.
They are called SN1 because the rate of the reaction is based on the carbocation. rate= k[+]
3o > 2o NO 1o
Step 1
Rate Limiting Material
Mixture of R and S
Neclophillic Subsitution Reaction
SN2 SN2 Reactions are a One step reaction.
They are called SN2 because the rate of the reaction is based on the carbocation. rate= k[Starting Material][Nuc]
1o > 2o Typically no 3o
Product inversion (R S)
Elimination Reactions
Elimination reactions are just like the SN reactions, except you get a double bond instead of a substitution.
Consider the reaction.
CH2
CH3
H3C Br
H-Br
H CH2
CH3
H3C +
CH2
CH3
H3C OH
H
-OH
-OH
CH2
CH3H3C
Esters
Esters are an important class of compounds made by nuclephilic substitution.
Esters are a diverse class of compounds that have a variety of functional attributes useful to the cosmetic chemist.
The functionality is determined by the structure. The ester reaction in simple form.
Esters
Reactants Acid & Base – High Acid Value & Hydroxyl value. Saponification value is low.
Products Acid Value and Hydroxyl value are low Saponification value is High
Structurally,1. Direct esterification
2. Transesterification
Direct Esterification
This Ester is made from an Acid and Alcohol.
CH3CH2OHHO
OCH3(CH2)3
+OCH2CH3
O
CH3(CH2)3
+ HOH
HO+
Palmitic Acid Isopropyl AlcoholIsopropyl Palmitate
Trans-Esterification
This type of ester is made from by reacting an Ester and Alcohol.
You always get a mixture of Esters but can separate with packed column.
CH3CH2OHOCH3
O
CH3(CH2)3
+OCH2CH3
O
CH3(CH2)3
+ CH3OH
Trans-Esterification
This Ester is made from an Triglyceride and Alcohol.
CH2OH CH3(CH2)10C(O)OCH2 | | CHOHCH3(CH2)10C(O)OCH + 3 CH3(CH2)11OH -> CH3(CH2)10C(O)O(CH2)11CH3 + | | CH2OHCH3(CH2)10C(O)OCH2
Triglyceride Alcohol Ester Glycerin
Trans-Esterification
Triglyceride and Alcohol.
Esters may also be prepared by the reaction of a triglyceride with a fatty alcohol, releasing glycerin. Glycerin is often removed by allowing it to settle from the ester and decantation. This reaction is generally conducted using acid or metal catalyst.
Trans-Esterification
Question
How would an ester made from an acid, in the direct process differ from the same ester made by transesterification using either methyl ester or triglyceride?
Types of Esters
The structure of Esters fall into three categories:
1. Simple
2. Complex
3. Polyesters
Simple Ester
OR1
O
CH3(CH2)3
This type of ester is made from a mono-acid and mono-Alcohol
Consider
OCH3
O
CH3(CH2)8
Name? IUPAC ? INCI?
Simple Ester
OCH3
O
CH3(CH2)8
Raw Materials?
1. Find the weak spot of the molecule
2. Break the molecule and see what it is
OCH3
O
CH3(CH2)8 HOCH3OH
Complex Esters
CH2OH | HO-CH2-C-CH3
| CH3
Neopentyl glycol (NPG)
CH2OH | HO-CH2-C-CH3
| CH3
R
O
RO CH2O
| O-CH2-C-CH3
| CH3
You can have a mono-ester or a di-ester
Complex Esters
Di-Pentaerythritol (DPE) 6 hydroxyl groups CH2OH CH2OH | | HO-CH2-C-CH2-OCH2-C-CH2OH | | CH2OH CH2OH
An Example
OCH2-C-CH2O
CH2O
CH2O
(CH2)10CH3O(CH2)10CH3
O(CH2)10CH3
OCH3(CH2)10O
Pentaetyrthritol
Name?
tetralaurate
Why is the name Laurate?
Another Example
OCH2-C-CH2OH
CH2O
CH2O
(CH2)10CH3
O(CH2)10CH3
OCH3(CH2)10O
Name? Pentaetyrthritol trilaurate
Question
Now for the real question…..
How would you expect the two to function differently in formulations?
OCH2-C-CH2O
CH2O
CH2O (CH2)10CH3
O
(CH2)10CH3
O
CH3(CH2)10
O
(CH2)10CH3
O
OCH2-C-CH2OH
CH2O
CH2O (CH2)10CH3
O
(CH2)10CH3
O
CH3(CH2)10
O
Problem
Stearic Acid CH3(CH2)16COOH
Lauryl Alcohol CH3(CH2)11OH
Lets make 200 g of Lauryl Stearate
Determine the Formula of the reactants
O(CH2)11CH3
OCH3(CH2)16
Problem
Determine MW Reactants
Stearic Acid CH3(CH2)16COOH C18H36O2
C18*12 =216 H36 1*36 =36 O2 2*16= 32
216+36+32 = 284
Lauryl Alcohol CH3(CH2)11OH C12H24O
C12*12 = 144 H24 1*24 = 24 O 1*16= 16
144+24+16 = 184
Problem
Determine Mole Ratio and %
Material MW MR MCH % Grams
Stearic Acid 284 1.0 284 60.6 121.2
Lauryl Alcohol 184 1.0 184 39.4 78.8
Total 468 100.0 200.0
In theory there will 3.8% Water generated and 96.2 % Ester at 100% Rxn
Amide
Amides are an important class of compounds made by nuclephilic substitution.
Amides are a diverse class of compounds that have a variety of functional attributes useful to the cosmetic chemist. Alkanolamides are a diverse class of compounds, used
commonly in personal care to alter the salt curve of formulation and provide a thickening effect to the formulation
The functionality is determined by the structure. The Amide reaction in simple form.
Direct Amidation
This Amide is made from an Acid and Amine.
CH3CH2NH2HO
O
CH3(CH2)3
+NHCH2CH3
O
CH3(CH2)3
+ HOH
Reactants
Acid Value & Alkali Value are HIGH
Products
Acid Value & Alkali Value are LOW
Saponification Value- Increases
Amide Types
Structurally amides fall into two categories based upon alkanolamine type: 1. Monohydroxy -amines (monoethanolamine,
monoisopropanolamine)
2. Dihydroxyamines (diethanolamine, diisopropanolamine)
3. There are no amides based upon tertiary amines.
Additionally, within each category amides can be classified by the fatty raw materials and can be:1. Saturated
2. Unsaturated
3. Branched
4. Guerbet
Amide from Methyl Esters
Methyl ester is reacted with ethanolamines, releasing methanol.
The use of the methyl ester for amid synthesis offers the most flexibility in obtaining pure carbon numbers in the product. Methyl esters can be fractionated easily and almost any carbon number methyl ester can be used to make unique products.
Methanol is removed by distillation leaving behind the amid. This reaction is generally conducted using base catalyst. Methanol, a flammable liquid, must be efficiently removed to obtain a high purity product. Air must be excluded to prevent color formation.
Direct Amidation
This Amide made from an Ester and Amine.
CH3CH2NH2OCH3
O
CH3(CH2)10
+NHCH2CH3
O
CH3(CH2)10
+ HOCH3
Methyl Laurate Ethylamine N-Ethyl Lauramide Methanol
Specifications
Amine Value – Amine value is a measure of the unreacted amine content. It will drop as the reaction proceeds.
GLC- The ratio of carbon distribution of the amid can be determined by GLC. The distribution is critical to performance.
Color – This is a good indication of the way in which the product was made. Darker colors generally indicate that the product was exposed to more heat and consequently may have more oxidation.
FTIR – This instrumental method is a great method to develop a fingerprint for the product. The availability of analytical programs to look at numerical comparisons to a standard pre-approved lot offers the chemist a unique method of verifying batch-to-batch variability.
Melt point – The melting temperature is an important property to check
% Glycerin – Even in instances where there is an acid value, it is critical to check glycerin content to determine is the acid was added to a product made by reaction of a triglyceride.
Amide from Fatty Acids
Fatty Acid is reacted with an ethylamine, releasing water. Water is removed by distillation leaving behind the amid. This reaction is generally conducted without catalyst. . Water must be efficiently removed to obtain a high purity product. Air must be excluded to prevent color formation.
CH3CH2NH2HO
O
CH3(CH2)10
+NHCH2CH3
O
CH3(CH2)10
+ HOH
Amide from Fatty AcidsSpecifications
Acid Value – Acid value measures added acid. Acid reacts with amine to form amid. In cases of esters made by transesterification, there will be no acid value, unless the acid is post added, that is added after the making of the product.
Amine Value – Amine value is a measure of the unreacted amine content. It will drop as the reaction proceeds.
GLC- The ratio of carbon distribution of the amid can be determined by GLC. The distribution is critical to performance.
Color – This is a good indication of the way in which the product was made. Darker colors generally indicate that the product was exposed to more heat and consequently may have more oxidation.
FTIR – This instrumental method is a great method to develop a fingerprint for the product. The availability of analytical programs to look at numerical comparisons to a standard pre-approved lot offers the chemist a unique method of verifying batch-to-batch variability.
Amide from Triglycerides
A triglyceride is reacted with an alkanolamine, releasing glycerin. Glycerin is not removed and is left in the product in which it is soluble. This reaction is generally conducted using a base catalyst.
Specifications
Acid Value – Acid value measures added acid. Acid reacts with amine to form amide. In cases of esters made by transesterification, there will be no acid value, unless the acid is post added, that is added after the making of the product.
Amine Value – Amine value is a measure of the unreacted amine content. It will drop as the reaction proceeds.
GLC- The ratio of carbon distribution of the amid can be determined by GLC. The distribution is critical to performance.
Oolor – This is a good indication of the way in which the product was made. Darker colors generally indicate that the product was exposed to more heat and consequently may have more oxidation.
FTIR – This instrumental method is a great method to develop a fingerprint for the product. The availability of analytical programs to look at numerical comparisons to a standard pre-approved lot offers the chemist a unique method of verifying batch-to-batch variability.
Melt point – The melting temperature is an important property to check.
% Glycerin – Even in instances where there is an acid value, it is critical to check glycerin content to determine is the acid was added to a product made by reaction of a triglyceride.
Problem
Lets Make 200 g of Lauramide DEA
Determine the Formula of the Reactants
Lauric Acid CH3(CH2)10COOH
Diethanolamine N-(CH2CH2-OH)2
NH(CH2)2OH
O
CH3(CH2)10
Problem
Determine Emp Formula
Lauric Acid CH3(CH2)10COOH C12H24O2
Diethanolamine N-(CH2CH2-OH)2 C4H10N
Problem
Determine MW Reactants
Lauric Acid CH3(CH2)10COOH C12H24O2
C12*12 = 144 H24 1*24 = 24 O2 2*16= 32
144+24+32 = 200
Diethanolamine N-(CH2CH2-OH)2 C4H10O2N
C12*4 = 48 H10 1*10 = 10 N 1*14= 14
48+10+14+32 = 104
O2*16 = 32
Problem
Determine Mole Ratio and %
Material MW MR MCH % Grams
Lauric Acid 200 1.0 200 65.8 131.6
DEA 104 1.0 104 34.2 68.4
Total 304 100.0 200.0
There will theoretically be 5.9 % water generated and 94.1% Amide, if there is 100% reaction
CarboxylatesSoap from Methyl Ester
Methyl Esters are saponified by reaction with KOH. The methanol produced is generally distilled from the product.
KOHOCH3
O
CH3(CH2)10
+O-
O
CH3(CH2)10
+ HOCH3K+
Potassium Laurate
CarboxylatesSoap from Methyl Ester
Methyl Esters are saponified by reaction with KOH. The methanol produced is generally distilled from the product.
KOHOCH3
O
CH3(CH2)10
+O-
O
CH3(CH2)10
+ CH3OHK+
Potassium Laurate
CarboxylatesSoap from Triglycerides
This reaction is used to produce the so-called glycerin soaps. The reaction produces three moles of soap and one mole of glycerin. The glycerin stays in the soap and alters hardness of the soap giving the characteristic glycerin soap feel.
Soap Specifications
Acid Value – Acid value measures added acid. Acid reacts with base to form soap. In cases of esters made by transesterification, there will be no acid value, unless the acid is post added, that is added after the making of the product
Alkali Value – Alkali value is a measure of the unreacted base content, added to saponify the oil. It will drop as the reaction proceeds.
Color – This is a good indication of the way in which the product was made. Darker colors generally indicate that the product was exposed to more heat and consequently may have more oxidation.
FTIR – This instrumental method is a great method to develop a fingerprint for the product. The availability of analytical programs to look at numerical comparisons to a standard pre-approved lot offers the chemist a unique method of verifying batch-to-batch variability.
Melt point – The melting temperature is an important property to check
% Glycerin – Even in instances where there is an acid value, it is critical to check glycerin content to determine is the acid was added to a product made by reaction of a triglyceride.
Carboxylatesfrom Fatty Alcohols
Sodium mono-chloroacetate is reacted with fatty alcohol or fatty alcohol ethoxylate in the presence of sodium methylate catalyst. Chloride ion is produced, which forms sodium chloride. Sodium chloride, a crystalline solid, is filtered off.
CarboxylatesFatty Alcohol
Category Specification
INCI Name Trideceth-7 Carboxylic acid
Appearance Clear Amber Liquid
Color, Gardner 3 Max
Acid Value 45.0 – 52.0
% Solids 90.0 – 92.0
pH (1 % DI water) 3.0 – 4.0
Solubility (DI water) Cloudy, translucent
NaCl 1.0 % Max
Betaines
Amido betaines are prepared by the reaction of sodium mono chloroacetate with an amido tertiary amine. Sodium chloride is produced.
Problem
Next Determine Formula of Reactants
Lauramidopropyl dimethylamine C17H36ON2
Sodium monochloroacetate C2H2O2Na Cl
Problem
Determine MW Reactants
Lauramidopropyl dimethylamine C17H36ON2
C12*17 =204 H36 1*36 = 36
O 1*16= 16 N2 2*14=28
204+36+28 = 268
Sodium monochloroacetate C2H2O2Na Cl
C2*12 = 24 H2 *1= 2 O2*16=32 Na 23*1 Cl 36*1=36
24+2+32+23+36=117
Problem
Determine Mole Ratio and %
Material MW MR MCH % Grams
Lauryl DMAPA 268 1.0 268 69.6 139.2
Sodium monochloroacetate 117 1.0 117 30.4 60.8
Total 385 100.0 200.0
Problem
Adjust for water (60% water)
Material MW MR MCH % Grams
Lauryl DMAPA 268 1.0 268 69.6 139.2Sodium monochloroacetate 117 1.0 117 30.4 60.8Total 385 100.0 200.0
Material 100 % 40%Lauryl DMAPA 69.6 * .40 27.85 Sodium monochloroacetate 30.4 * .40 12.15 Water 60.00Total
Problem
Adjust for water (60% water) Material MW MR MCH % GramsLauryl DMAPAS 268 1.0 268 69.6 139.2Sodium monochloroacetate 117 1.0 117 30.4 60.8Total 385 100.0 200.0
Material 100 % 40%Lauryl DMAPA 69.6 * .40 27.85 Sodium monochloroacetate 30.4 * .40 12.15 Water 60.00Total
% NaCl is 4.2% for 40% Active
Amino Propionates
These products are a type of amphoteric surfactant that are capable of existing in a cationic, anionic and zwitterionic form depending upon pH.
This separates them from betaines, which are amphoteric surfactants that cannot exist in the anionic form.
The products are made by the reaction of a primary amine with two moles of acrylic acid in aqueous solution.
Additionally, unlike betaines these products do not have salt produced during the reaction and consequently are salt free.
Quats
Quats, or more formally, quaternary compounds are tetra-substituted ammonium compounds. The generic formula is as follows; R2 | R1-N+-R3 M-
| R2
R1 is generally alkyl or alkylamido. R2 most often is methyl, or hydroxy ethyl. R3 is commonly methyl, ethyl, or benzyl.
The exact nature of the “R” groups dictates performance.
The M is a counter-ion needed for charge balance and is generally either Cl, or CH3SO4.
Chloride Quat
Quaternary compounds, or simply quats are cationic compounds. This class of materials find a wide range of applications, including conditioning of hair and skin and germicidal compounds. The reaction is one in which a tertiary amine is reacted with an organic chlorine containing compound for example benzyl chloride to produce a quat liberation inorganic chloride ion.
Chloride Quat
Germicidal Quats include: Benzalkonium chloride Cetyl trimethylammonium bromide Cetylpyridunium chloride Cetylpyridinium chloride Benzethonium chloride
Sarcosinates
Sarcosinate surfactants are mild, biodegradable anionic surfactants derived from fatty acyl chlorides and sarcosine.
These compounds features lather building and resistance to sebum delathering in cleaners, polymers, industrial chemicals, petroleum and lubricant products.
Sarcosinates are used as a foaming and cleansing agent for shampoo, shaving foams and foam washes and is soap bars to take advantage of the excellent lather and skin feel contribution.
SO3,prepared by the burning of sulfur, is reacted with fatty alcohol giving the fatty sulfate sauer ester, which is neutralized in a subsequent step water by hydroxide ion, most commonly with sodium as the counter ion. Potassium ammonium and even lithium salts have been prepared.
Electrophilic SubstitutionSulfonation
Special Requirements
SO3 is a very reactive corrosive and noxious material. Commonly SO3 is made by burning sulfur just prior to sulfation.
The use of SO3 in making products is not recommended since very specialized reactors and handling equipment are needed.
Electrophilic SubstitutionSulfonation (CSA)
Chlorosulfonic acid, a liquid, is reacted with fatty alcohol giving the fatty sulfate sauer ester, and unlike the SO3 version HCl.
The HCl is removed via vacuum and reacted with water to make aqueous HCl.
To the extent the HCl is not removed the product has NaCl after neutralization.
Chlorosulfonic acid (CAS), while easier to handle than SO3 is likewise a very reactive corrosive and noxious material. If it comes in contact with water it liberates HCl gas. It can cause a fire in contact with celluosics. The use of CSA in making products needs to be conducted under very specific anhydrous conditions, and the resulting HCl gas needs to be removed and disposed of properly. Consequently, very specialized reactors and handling equipment are needed.
Special Requirements
Cyclo-addition reactions
There are a set of rules called the Woodward Hoffmann Rules Essentially they determined that the pathway of
concerted pericyclic reactions were determined by the symmetry properties of the orbitals that were directly involved.
Reactions involving 4n + 2 electrons will be thermogenically allowed
(heat) 4n electrons will be photogenically allowed
Diels-Alder Reaction
This reaction is a reaction involving a Diene (4 electrons) and a Dienophile (2 electrons)
All you need is heat!
2 + 2 clycoaddition
These types of reactions are photochemically allowed.
All you need is hν light.
+
R1
R2
R1
R2
Dimer Acid
Dimer acid describes a reaction mixture that is composed of a series of substituted cyclohexene-dicarboxylic acids formed by the Diels-Alder reaction. The reaction requires a dienophile and a diene. The mixture of products is a consequence of the various isomers that can occur with the reaction. Commercially, the product is made using tall oil fatty acid, derived from pine trees. This material has roughly the proper stiochometric ratio of diene ( linoleyl) to dienophile (oleyl).
Click Chemistry
“Click Chemistry” is a concept pioneered by Barry Sharpless, seeks to define the “ideal” chemical reaction. Give High Chemical Yields Produce few or no toxic byproducts Be stereospecific Produce products that are physiologically stable Have simple reaction conditions.
http://vimeo.com/46865607
Ring OpeningAlkoxylation
Lower molecular weight epoxides (oxiranes) such as ethylene oxide, propylene oxide and butylene oxide are capable of reacting with hydroxyl generally under base catalysis, causing a ring opening and an addition of oxyalkylene group
Reaction with ethylene oxide adds polyoxyethylene groups, with propylene oxide adds polyoxypropylene groups and with butylene oxide adds polyoxybutylene groups.
All these groups and mixtures thereof bring new solubility properties to the compounds to which they are added. The resulting compound likewise contains a hydroxyl group so a variety number of moles of oxide can be added.
Lower molecular weight oxiranes are very reactive and the safe and efficient utilization of these materials require rigorous chemical engineering, advanced materials handling technology and innovative catalyst technology
Ring opening reaction is a reaction where a ring is open or broken. Ethoxylation Propoxylation Carboxylation (anhydrides)
Ring Opening
Alkoxylation
Ethoxylation is the reaction of an alcohol with ethylene oxide, producing a R-O-(CH2CH2O)xH
Propoxylation is the reaction of an alcohol with propylene oxide, producing a R-O-(CH2CHO)xH | CH3
If a molecule has two reactive groups on it, it can form cyclics.
The reactive groups have to be the correct number of carbons apart. 6 > 5 > 7
How about a molecule that has an Alcohol and acid?
HO
O
OHO
O
+ HOH
12
3
4
56
Lactone
Description: The preparation of lactams from ether amine and butryolactone actually occurs in two distinct steps. The first is ring opening of the butryolactone by nucleophilic attack of the carbonyl by the ether amine. The second is ring closure, making water and a cyclic amid, commonly called a lactam.
Are molecules that are cyclic amides
LactamsHO
O
NHH2N
O
+ HOH
Lactam
Ring Closing Reactions
Imidazoline
Description: Amino ethyl ethanol amine (AEEA) is reacted with a fatty acid to produce an amide with a free amino group. Subsequently, the ring is closed at high temperature producing a second mole of water.
Ring Closing Reactions
Note: The first reaction (amid formation) occurs at about 180oC. The second occurs as the temperature is increased to 200oC. Efficient removal of water is necessary to obtain a high purity (90%+) product.
Sorbitan Esters
Sorbitol, a hexose sugar, is cyclized by dehydration to form the 1:4 sorbitan structure.
Esterification occurs mainly at the side-chain OH group, but some occurs at the ring OH's.
Sorbitan esters are products made the reaction of sorbitol and fatty acids. Sorbitol is generally provided as a 70% solution in water. The reaction actually includes three distinct steps. They are (1) removal of water, (2) cyclization of linear sorbitol to make sorbitan and (3) esterification of the sorbitan with a fatty acid. Many modern techniques make the product in one batch running the first step in the presence of all the raw materials, then cyclizing and esterifying in tandem
Alkylpolyglucoside
Description: Alkylpolyglucoside or APGs have been known for many years. If fact in 1893, the German chemist Emil Fischer combined fatty alcohols and glucose obtained from coconut or palm kernel oil and corn for the first time in 1893. However, it took almost one hundred years, to commercialize these products
If a molecule has two reactive groups on it, it can form
Why is ring closing a problem?
4
1
23
5
6O
O +
OO
-
O
O
Tutomerization
Tautomers are isomers that interconvert by a chemical reaction called Tautomerization.
Why is this reaction important?
Everything we have done so far has dealt with the formation of Carbon-R bonds, but what about Carbon-Carbon bonds?
The most common why to do this involves an Enol
What is a Enol?
R
O
HBase
R
O-
Enol
Enol Reactions
1. Enol reacted with an acid
2. Enol with an Ester
RO-O
OHO
RO
+ H2O
R
O-O
OR1
O
R
O
+ HOR1
+
+
Guerbet Reaction ( an Aldol Condensation)
Under the proper conditions, linear alcohols can be oxidized to aldehydes, undergo an aldol condensation and produce Guerbet alcohols. The class of materials has been known for many years. Guerbet alcohols are regio-specific beta branched oils that are liquid to very low temperatures. They are super-fatting agents and are used to make a variety of esters.
Amine Oxides
An amine oxide, also known as amine-N-oxide and N-oxide, is a chemical compound that contains the functional group R3N+-O− (sometimes written as R3N=O or R3N→O).
In the conventional formula assigned to the amine oxides R3N→O, the link uniting the nitrogen and oxygen atoms is a semipolar bond.
The term amine oxide applies only to oxides of tertiary amines including nitrogen-containing aromatic compounds like pyridine. A tertiary amine is reacted with 35% peroxide in aqueous solution. The product is an amine oxide.
Amine Oxides
-Typical Specifications Appearance Provides a general indication of heat history and product quality
Amine Oxide Active Measures puritypH (10% Sol.) Measures pH an important indication of product ionic nature.
Free Peroxide Measures unreacted H2O2 and consequently % reaction.
Free Amine Measures unreacted amine and consequently % reaction.
Color (APHA) Provides a general indication of heat history and product quality.
Reduction
Perhaps one of the most important and commonly overlooked reaction class is a group of related reactions called reduction. Within the class are several key reaction types,1. hydrogenation,
2. hydrogenolysis and
3. reduction.
The commonality is the fact that hydrogen is reacted with various organic materials in the presence of a catalyst and most often a solvent.
As will become clear the choice of organic material, solvent and catalyst has a profound impact on the product obtained.
Hydrogenolysis
Hydrogenolysis is a process in which hydrogen, in the presence of a suitable metal catalyst reacts with an organic compound breaking it into two molecules that are in low oxidation state ( for example a ethyl ester to two alcohols).
Group Specific Hydrogenolysis
This reaction allows for the reduction of the methyl ester while keeling the vinyl group in tact. The process relies upon specific catalysts developed to have this specificity. This reaction is used to make commercial oleyl alcohol and related materials.
What are Polymers?
Polymers are macromolecules Poly = Many -mer = Parts
Typically Polymers can be: Natural Synthetic
Brief History
“Polymer” was first used by Berzelius in 1833.
In 1839, Charles Goodyear discovered vulcanization, by combining natural rubber with sulfur and hearting it to 270 °C
The first truly synthetic polymer used on a commercial scale was phenol-formaldehyde resin by Baekeland, “bakelite”.
In 1920, Staudinger: Polymers are high molecular weight molecules. (Nobel Prize
in 1953) The Prevailing Theory: Polymers were aggregates of small molecules.
“Drop the idea of large molecules. Organic molecules with a molecular
weight higher than 500 do not exist”
-Advice given to Hermann Staudinger
Polymer chemistry
Polymer chemistry is organic chemistry on a much larger scale.
It involves the reaction of molecules or monomers with at least two reactive sites. Free radical chemistry involves double bonds.
When the molecular weight of polymers is increased, the mechanical and chemical properties of the polymers will drastically change.
Nylon Rope Trick
The polymerization is so quick that when the two materials come into contact, they instantly form a polymer.
New Terms
Structural Unit or Monomer Unit: The monomer or the residue from the monomer.
Repeat unit: the unit enclosed in the brackets.
Homo Polymer: Polymer formed by one monomer.
Hetero polymers or copolymers: Contain more than one atom type in the bracket unit.
Degree of Polymerization (DP or Xn): The total number of structural units in the polymer chain.
Polydispersity (PDI): Polymer are polydisperse meaning they have many different polymer chain lengths.
Polymer Nomenclature
Based on the Monomer:
PolyX
If “X” is a single word, the name of the polymer is is written out directly
If “X” consists of two or more words, parentheses should be used.
Poly(vinyl chloride) (PVC) is made by the polymerization of vinyl chloride
CH2=CHCl
Polymer Nomenclature
Based on polymer Structure The most common method for condensation
polymers since the polymer contains different functional groups than the monomer.
Common Functional Groups….
Polyesters
Polyamides
Definitions
Thermoplastic: Polymers that are not cross-linked can melt and flow, can dissolve.
Step growth polymers: They are called step growth because the monomer adds on either chain end. Molecular weight builds slowly, high molecular weight only at high conversion.
Chain Growth Polymers: New monomers add to the chain end only. Every reaction adds to the molecular weight.
Molecular Weight
Since this is polymer chemistry, we will consider a very realistic, everyday example to explore Molecular weight……
10,000 lbs1 lbs
Polydispersity (PDI)
So how can we tell which molecular weight do we use? Both Mn & Mw have value, but how do we apply them to a polymer sample?
In Polymer science it is common to use the ratio of the weight average to the number average as a measure of the breadth of the distribution rather than the moments and this ratio is called the polydispersity.
Molecular Weight
First we have to understand a basic principle in polymer chemistry
Hydrodynamic volume of a polymer in solution
GPC
This technique is an INDIRECT method for determining molecular weight
It is based off of comparing the Hydrodynamic Volume of your polymer in solution to the Hydrodynamic Volume of a series of Polymers of known size and distribution (Standard).
The polymer is dispersed into a solvent and passed though a column, based on the size of the polymer, the elusion time will be different
GPC
It is important to note that:
If you take 3 polystyrene samples of the exact same MW, but have different polymer structure (branched, linear, comb-like) they can elute at DIFFERENT TIMES!!!
Also, if you have have 2 polymers of the exact same MW, one Polystyrene and the other one PMMA. They can elute at DIFFERENT TIMES!!!!
Luckily for us Benoit and co-workers came up with a Universal Calibration Curve.
Based on:
The product of Intrinsic Viscosity & MW was directly proportional to Hydrodynamic Volume.
Tm and Tg
Polymeric materials are characterized by two major types of transition temperatures- The crystalline melting temperature (Tm) and the glass transition temperature (Tg)
Tm : the melting temperature, just like a traditional small molecule.
Tg : The temperature at which the amorphous domain of a polymer take on the characteristic properties of the glassy state = brittle, stiffness and rigidity.
Free Radical Polymerization
There are several steps involved in the polymerization process. Initiation Propagation Termination
Chain Growth Polymerization
This type of polymerization happens by a series of steps, most commonly a series of reactions.
Common Ester is formed when an acid is reacted with an alcohol, but what about a diacid and diol?
HOCH2CH2CH2OHHO
O
R1+
O
HO
O
R1
O
O OCH2CH2CH2O
n
HH
Controlled “Living” polymerization
There are a few techniques that can produce polymers with a PDI close to 1. Atom Transfer Radical Polymerization (ATRP) Reversible Addition-Fragmentation Chain Transfer
(RAFT)
There are some problems with the Controlled living, but these two are promising for the cosmetic world.
ATRP
O
R1
Cl + CuCl + Ligand
O
R1.
+ CuCl2 + Ligand
O
R1. +
O
O
O
O
OR1
.
O
O
O
R1. +
O
O
O
O
O
R1.
O
O
O
O
( )nCl
O
O
O
R1.
O
O
+ CuCl2 + Ligand O
O
O
R1
O
O
+ CuCl + LigandCl
• DEGMMA to MAPMA: 100 : 5• CuBr/HMTETA used as catalyst• DMF as a solvent• Polymer was purified by:
– Percipitation in hexanes– Passed through a short
neutral aluminum oxide/silica gel column
GPCMn = 43,000 g/mol
PDI = 1.13
Synthesis