ケイ素，ホウ素，スズ官能基を持つアリルパラジウム中間体を用いた触媒的炭素-炭素結合形成反応

抄録

π-Allylpalladium is usually recognized to serve as synthetically useful electrophilic allylating agents toward many nucleophiles. On the other hand, σ-allylpalladium possessing ligands that donate electrons acts as nucleophilic allylating agents toward electrophiles. We demonstrated the distinct reactivities of allylic gem-palladium/metalloid intermediates that could serve as C3 units in reactions other than allylation reactions by σ-allylpalladium. (1) Palladium-catalyzed highly stereoselective cyclopropanation of strained alkenes with organometalloid-substituted 1-arylallyl acetates. (2) Self-dimerization of Pd(0)-complexed 3-aryl or 2,3-diaryl vinylcarbenes generated from organometalloid-substituted σ-allylpalladium intermediates to provide 1,6-di- or 1,2,5,6-tetra-arylhexa-1,3,5-trienes. (3) Three-component reaction of 3-(pinacolatoboryl)- or 3-(n-tributylstannyl)allyl acetates, aldehydes, and organoboranes to afford the (Z)- or (E)-anti-homoallylic alcohols with excellent diastereoselectivity and good to high levels of alkene stereocontrol.