Fluorine-containing substituent groups

Table IV contains selected examples of the enzymatic resolution of esters with various structures. As was discussed above, enhancement of the optical purity was possible by changing the acyl group or the enzyme (Run 1,2 or 6,7). Noteworthy is the fact that acetate 5 with a trifluoromethyl group was converted by lipase MY into the alcohol with (R) absolute configuration without exception in every case, when the stereochemistry has been determined. However, substrates with the other fluorine-containing substituents furnished alcohols whose asymmetric configuration depended on their structures. Particularly interesting is the relationship between Runs 4 and 5 (18), when resolution was accompanied with simultaneous separation of diastereomers. To the best of our knowledge, this is the first example of the type of resolution of both diastereomers and enantiomers by enzymatic hydrolysis in a single transformation.

Military nerve agents are organophosphate componnds containing either a fluorine, sulfur, or cyanide substituent group (Dacre, 1984). GA contains a cyanide substituent group (VX contains a sulfur group and GB a fluorine group). The chemical synonyms. Chemical Abstract Service (CAS) and Army identification numbers (DA, 1974,1992 Dacre, 1984), and chemical formula for GA are as follows ... 

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