Gas Chromatography (GC) (IUPAC Compendium of Chemical Terminology):

Lecture 3. Gas chromathography.
Reagents for alkylation.
H C
N CH 3 3
H O O CH 3
C
3
DMF-DMA – N,N-dimethylformamidedimethylacetal. Methylation
with DMF-DMA can be applied for fatty acids, primary amines and
(partially) amino acids forming N-dimethylaminomethylene amino acid
methyl esters.
H 3
C
S + CH 3
H 3
C
OH
TMSH – 0.2 M trimethylsulfoniumoxide in methanol. Methylation with
TMSH is recommended for free acids e.g. fatty acids ,
chlorophenoxycarboxylic acids , their salts and derivatives as well as
for phenols and chlorophenols, which can be detected in very small
amounts. One great advantage is simplification of the sample
preparation. Lipids or triglycerides can be converted to the
corresponding fatty acid methyl esters (FAMEs) by a simple
transesterification.
31