Abstract
(Trimethylsilyl)methyl carbamates were prepared from (trimethylsilyl)methanol and N ,N -dialkylcarbamoyl chlorides and were metalated by s- BuLi/TMEDA. The configurationally labile lithiated carbamates were reacted with borates derived from (+)-pinane-2,3-diol to give boronates diastereoselectively (yields up to 84%, dr up to 17:1). The absolute configurations at the boron-bearing carbon atoms of three boronates were assigned by single crystal X-ray structure analyses.
Key words
carbamates - carbanions - lithiation - nucleophilic substitution - diastereoselectivity
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