総説・解説等

The hydrosilylation of oxygen-containing olefins in the presence of Co2(CO)8 was carried out. The Co2(CO)8-catalyzed hydrosilylation of allyl acetate with HSiEt2Me is consistent with proceeding via a silylmetalation mechanism rather than a classical hydrometalation (Chalk-Harrod mechanism).

The reaction of aromatic nitriles with triethoxyvinylsilane proceeded in the presence of a Ru(H)2(CO)(PPh3)3-catalyst to give the corresponding C-H/olefin coupling products in high yields. The nitrile group is capable of directing the ruthenium to the ortho C-H bond via π-bonded mode.

The addition of a β C-H bond to the formyl group of aldehydes to olefins took place with the aid of Ru(H)2(CO)(PPh3)3 as a catalyst. Several olefins can be used in the catalytic reaction of conjugate enals. The presence of a sterically hindered substituent at the ortho position of benzaldehyde and the presence of an electron donating substituent appear to be important factor in accomplishing the desired coupling reaction.

The ruthenium- and rhodium-catalyzed intramolecular C-H/olefin coupling reactions of 1-(2-pyridyl)-1,5- and 1,6-dienes proceeded regio- and stereoselectively to give 5- or 6-membered ring products.

Catalytic functionalization of unreactive C-H bond has become one of the most attractive research subjects in modern organic chemistry. To date, a variety of catalytic reactions involving C-H bond cleavage have been reported. In this review, we briefly survey the reported research with respect to efficient and selective transition-metal-catalyzed C-C bond formation via C-H bond cleavage.