2- Trimethylsilyl-l,3-propanediol

Hydroboration of Silylalkenes and SUylalkynes. (Z)-l-Trimethylsily 1-1-alkenes react with DBBS to produce ge/rniime-talloalkanes, which upon oxidation afford alcohols containing the trimethylsilyl group in high yields (72-84%) (eq 13). Unexpectedly, desilylation of (2)-2-(l-trimethylsilyl-l-hexenyl)dibromo-borane is observed during the hydrolysis followed by treatment with 1,3-propanediol. 

S)-l-Alkyl-1,2,3,4-tetrahydroisoquinolines. The bis(trimethylsilyl) ether (2) of 1 has been used as a chiral auxiliary to effect alkylation of tetrahydroisoquinoline (equation I) with high enantioselectivity. The chiral propanediol is much more effective than (R)-(-)-a-phenethylamine, and moreover leads consistently to (S)-l-alkyl derivatives. 

Identification of N-acetyl-g-(p-tolyloxy)alanine in the urine of rats treated with 3-(p-tolyloxy)-l,2-propanediol. The Mephenesin analogue, 3-( -tolyloxy)-l,2-propanediol was administered to rats and urinary metabolites were identified by GC-MS. In the alkaline extracts, the unchanged substance was the major component. Fig. 1 (top) shows the gas chromatographic patterns of acidic extracts from the urine of rat treated with 3-( -tolyloxy)-1,2-propanediol. For derivatization, hexamethyldisilazane was used as the trimethylsilylating agent. The column temperature was programmed from 200 C at 3 C/min. The large peak pointed by a small arrow was identified as B-( -tolyloxy)-lactic acid. 

Identification of N-acetyl-3" phenoxyalanine in the urine of rats treated with 3-phenoxy-l,2-propanediol. The other Mephenesin analogue, 3-phenoxy-l, 2-propanediol was given to rats and the urine sample was analyzed by GC-MS. In the alkaline extracts, the main component was 3-phenoxy-l, 2-propanediol. The gas chromatogram of the acidic extracts was obtained after trimethylsilylation (shown in Fig. 1, bottom). A major metabolite was 3 phenoxylactic acid corresponding to the large peak indicated by the small arrow. 

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