S-Ethyl trifluorothioacetate

S-Ethyl trifluorothioacetate [383-64-2] M 158.1, b 88-90 /atm, 90.5 /760mm, dj 1.255, Dp 1.372. If IR is free of OH bands then fractionate, but if OH bands are present then dilute with dry Et20, wash with 5% KOH and H2O, dry over MgS04 and fractionate through an efficient column [Hauptschein et al. J Am Chem Soc 74 4005 1952]. Powerful obnoxious odour. 

Wolfrom and Conigliaro4 found that S-ethyl trifluorothioacetate selectively acylates the amino group of 2-amino-2-desoxy-D-glucose (methanolic sodium methoxide, 24 hours, room temperature, 73% yield). They used this protective group in the synthesis of purine nucleosides. The group was removed by means of methanolic ammonia. (Note that purine nucleosides are unstable to acid.)... 

Thus other trifluoroacetylation reagents have been investigated. S-Ethyl trifluorothioacetate [Ethanethioic acid, trifluoro-, jS-ethyl ester] has none of the above disadvantages. It does require, however, weakly basic conditions (pH 8-9) and an aqueous medium. Phenyl... 

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