Catalytic C-H/olefin coupling can be directed by N,O-heterocyclic substituents. The Ru3(CO)12-catalyzed reaction of 4,4-dimethyl-2-(2-methylphenyl)-5,6-dihydro-4H-1,3-oxazine (1) with triethoxyvinylsilane gave a mixture of the corresponding 1:1 addition product (3a) and its olefinic analogue (3b) in good yields in ca. a 1:1 ratio. In the case of the reaction of 4,4-dimethyl-2-(2-methylphenyl)-4,5-dihydro-1,3-oxazole (7), the olefinic analogue (8b) of the coupling product (8a) was obtained as the major product. The existence of a new reaction pathway is discussed.

[reaction: see text] The viability of hydroxylamines as nucleophiles in transition-metal-catalyzed allylic substitutions was examined. We have found that the oxygen atom of hydroxylamines having an N-electron-withdrawing substituent (also known as hydroxamic acids) acts as a reactive nucleophile. The palladium-catalyzed O-allylic substitution of hydroxylamines with allylic carbonate afforded the linear hydroxylamines. The selective formation of the branched hydroxylamines was observed in iridium-catalyzed reaction. Regio- and enantioselective allylic substitution of the unsymmetrical phosphates with hydroxylamines was studied by using the iridium complex of chiral pybox ligand. The aqueous-medium reaction with hydroxylamines proceeded smoothly in the presence of Ba(OH)(2).H(2)O to give the branched products with good enantioselectivities.

Catalyst-specific C-H/olefin as well as C-H/acetylene coupling has been accomplished for aromatics which contain both keto and imino substituents by simply changing the catalyst. By using Ru(H)2(CO)(PPh3)3 as the catalyst, the C-H bond at the position ortho to the carbonyl group reacted to add across an olefin. When Ru3(CO)12 is used as the catalyst, the C-H bond at the position ortho to the imino group reacted with the olefin.

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