Mitsuhiro Arisawa

A pure ruthenium hydride complex with N-heterocyclic carbene (NHC) ligand was efficiently generated from the reaction of a second-generation Grubbs ruthenium catalyst with vinyloxytrimethylsilane and unambiguously characterized. This ruthenium hydride complex showed high catalytic activity for the selective isomerization of terminal olefin and for the cycloisomerization of 1,6-dienes. These reactions of N-allyl-o-vinylaniline lead to novel synthetic methods for heterocycles such as indoles and 3

A ruthenium complex, generated from the Grubbs carbene catalyst with vinyloxytrimethylsilane, catalyzed the isomerization of terminal alkenes RCH2CHCH2 to internal alkenes RCHCHCH3. Application of this olefin isomerization to 2-(N-allylamino)styrene gave the corresponding enamines, which were converted into indoles by a standard ring-closing metathesis, see scheme (Ts=tosyl).

Ein Rutheniumkomplex, der aus dem Grubbs-Carbenkatalysator und Vinyloxytrimethylsilan hergestellt wurde, katalysiert die Isomerisierung von terminalen Alkenen RCH2CHCH2 zu internen Alkenen RCHCHCH3. Die Anwendung dieser Olefinisomerisierung auf ein geschütztes 2-(N-Allylamino)styrol führte zu den entsprechenden Enaminen, die durch eine Standard-Ringschlussmetathese in Indole überführt wurden (siehe Schema, Ts=Tosyl). Supporting information for this article is available on the WWW under http://

A novel hypervalent iodine(III)-induced direct intramolecular cyclization of alpha-(aryl)alkyl-beta-dicarbonyl compounds has been described. Both meta- and para-substituted phenol ether derivatives containing acyclic or cyclic 1,3-dicarbonyl moieties at the side chain undergo this reaction in a facile manner. The reactions afford benzannulated and spirobenzannulated compounds that are of biological importance. The reaction is found to be general, mild, and high yielding. The mechanism of the rea

M. Arisawa, S. Utsumi, M. Nakajima, N. G. Ramesh, H. Tohma and Y. Kita, Chem. Commun., 1999, 469 DOI: 10.1039/A809680E

Abstract We have developed a sulfur‐modified, gold‐supported palladium material (SAuPd) with palladium, Pd, nanoparticles on its surface; it is a recyclable, low‐leaching Pd catalyst. Here we report, using SAuPd, the first example of Pd nanoparticle‐catalyzed, unactivated C( sp 3 )H bond functionalization of amides, using 8‐aminoquinoline as a directing group, to yield ethynylated products. The low leaching properties of SAuPd enabled it to be recycled and reused 10 times for C( sp 3 )H bond f

An efficient synthetic method for the preparation of optically active pyrroloazocine, pyrroloazepine, quinolizidine, indolizidine using ring closing olefin metathesis (RCM) is described.

Non-metathesis reactions of ruthenium carbene catalysts, such as olefin isomerization, hydrogenation, radical reaction, activation of silane, cyclopropanation, epimerization cocyclopropane, [3 + 2] cycloaddition, and cycloisomerization, are summarized. The utility of these reactions was demonstrated by the synthesis of indole using olefin isomerization and subsequent ring-closing metathesis, the synthesis of indoline using cycloisomerization, and the synthesis of the putative structure of fistul

Chiral (-)-coniceine and (S)-pyrrolam A were synthesized from dienes prepared from L-proline by ring closure metathesis.

Azacycloundecenes, which are key intermediates in the synthesis of derivatives of the marine alkaloid manzamine C, are conveniently prepared using ring-closing olefin metathesis (RCM).

An efficient synthesis of alpha,beta-unsaturated ketones by the reaction of acid chlorides with trialkylaluminum (1/3 mole equiv) in the presence of AlCl(3) (1 mol equiv) is described. Dialkylzincs were also useful and are easier to prepare than trialkylaluminum. Reaction of RCOCl with R'AlCl(2) or R'(2)AlCl gave R'COR, without AlCl(3), in high yield.