Glycine betaine ammonium compounds

The study of these fluorine-containing salts was then extended, and we prepared other new compounds in this series, e.g. 2-fluoroethyl glycine hydrochloride and 2-fluoroethyl betaine hydrochloride (that is, carbofluoroethoxy-methyl trimethyl ammonium chloride). The first of these was readily prepared by the Fischer-Speier esterification of glycine with fluoro-ethyl alcohol ... 

Betaine is the tetra-methyl ammonium inner salt compound already referred to (p. 386). It is really a tri-methyl derivative of glycine. 

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