REGIOSELECTIVE CARBON-CARBON BOND FORMATION AT THE α-POSITION OF A SULFUR STABILIZED ALLYL CARBANION VIA AN ALKYLTHIOALLYLBORON “ATE” COMPLEX
Reaction of lithium alkylthioallylboron “ate” complexes (3), prepared from alkylthioallyllithium (1) and triethylborane at −78°C in ether, with carbonyl compounds proceeds via the attack at the α-position to produce the corresponding α-alkylated derivatives (4) in good yields.