Showing papers by "Fumitoshi Kakiuchi published in 1994"

Catalytic C-H/olefin coupling

Abstract: The cleavage and addition of ortho C-H bonds in various aromatic compounds such as ketones, esters, imines, imidates, nitrile, and aldehydes to olefins and acetlylenes can be achieved catalytically with the aid of ruthenium catalysts. The reaction is generally highly efficient and useful in synthetic methods. The coordination to the metal center by a heteroatom in directing groups such as carbonyl and imino groups is the key. The reductive elimination to form a C-C bond is the rate-determining step.

Efficient Catalytic Addition of Aromatic Carbon‐Hydrogen Bonds to Olefins.

Abstract: The selective cleavage of carbon–hydrogen bonds in organic compounds is a critical step in many organic syntheses, and is particularly important in the conversion of hydrocarbons to useful organic compounds. An organometallic ruthenium complex can cleave C–H bonds in a variety of aromatic systems, leading to addition to alkenes by C–C bond formation. The catalyst operates with a degree of efficiency, selectivity and generality that will make it extremely valuable in organic synthesis.

Completely Selective Synthesis of (E)‐β‐(Triethylsilyl)styrenes by Fe3(CO)12‐Catalyzed Reaction of Styrenes with Triethylsilane.

Abstract: Using Fe3(CO)12 as the catalyst, the reaction of styrenes (C6H5CHCH2, p-CH3C6H4CHCH2, p- ClC6H4CHCH2, and p-CH3OC6H4CHCH2) with triethyisilane gave (E)-β-(triethylsilyl)styrenes (2a, (E)-C6H5CHCHSiEt3; 2b, (E)-p-CH3C6H4CHCHSiEt3; 2c, (E)-p-ClC 6H4CHCHSiEt3; 2d, (E)-p-CH3OC6H4CHCHSiEt3) in 66–89% yields with complete selectivity. Similarly, Fe2(CO)9 also catalyzed dehydrogenative silylation again, with complete selectivity but in low yields. The reaction of styrene with treithylsilane, catalysed by OS3(CO)12, gave a mixture of the corresponding vinylsilane (dehydrogenative silylation product) and alkylsilane (hydrosilylation product).