CYCLOADDITIONS OF ALLYLSILANES, PART 11 - STEREOSELECTIVE SYNTHESIS OF HYDROXYCYCLOPENTANES AND HYDROXYMETHYLCYCLOBUTANES BY TITANIUM TETRACHLORIDE-PROMOTED [3-SILICON BOND(2]CYCLOADDITION AND [2+2]CYCLOADDITION OF STERICALLY HINDERED ALLYLSILANES AND SUBSEQUENT OXIDATIVE CLEAVAGE OF THE CARBON)

Even highly sterically hindered organosilicon compounds containing the bulky tert-butyldiphenylsilyl group can be oxidatively cleaved to the corresponding carbinols using a modified protocol of the original Fle ming-Tamao oxidation that generates the intermediate tert-butyldifluor osilyl derivatives. This novel application emphasizes the utility of a llyl-tert-butyldiphenylsilane as a building block for the stereoselect ive synthesis of either hydroxycyclopentanes or hydroxymethylcyclobuta nes via the sequence titanium tetrachloride-promoted cycloaddition and oxidative cleavage.