不飽和有機分子の触媒的ボリル化·シリル化の新展開：遷移金属触媒による精密反応制御と有機合成への応用

抄録

Transition-metal-catalyzed reactions for introduction of boryl and silyl groups into unsaturated organic molecules are described. Enantioselective silaboration of terminal allenes and silaborative C-C cleavage of meso-methylenecyclopropanes were achieved by a palladium catalyst bearing an optically active phosphorus ligand, (R)-2-bis(3,5-dimethylphenyl)phospino-1,1’-binaphthyl. New silylboronic esters bearing chloro, alkoxy, and dialkylamino groups on the silicon atoms were developed and used for silaboration of alkenes and alkynes. Intramolecular silaboration of alkenes was catalyzed by platinum complexes, in which the cis/trans selectivity of the resulting cyclic silyl ethers could be controlled complementarily by the phosphorus ligands on the platinum. In silaboration of terminal alkynes, complementary control of regio- and stereoselectivities were achieved. Silylboronic esters bearing diethylamino group on the silicon atom reacted as a silylene equivalent in the palladium-catalyzed reaction of terminal alkynes, 1,3-dienes, and 2-alkenylindoles to give silole derivatives. Dearomatizing conversion of pyridines was achieved by a palladium-catalyzed silaboration and a rhodium-catalyzed hydroboration. The boron- and silicon-containing compounds synthesized by the above-mentioned methods were utilized in C-C bond-forming reactions.