6a 6b of interest is the regioselectivity of the reaction of 2 with electrophiles. The a-silylallyl anion is known to react with electrophiles with y-selectivity, giving stereoselectively the (E)- vinylsilane 3.3 This is presumably due to the transoid stereochemistry of 4. Because of the cyclopentyl structure, the anion 2 has to adopt a cisoid stereochemistry. This stereochemical change may modify the regioselection of the reaction of the anion with electrophiles ( ...
