Kouichi Ohe

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNucleophilic substitution at the central allyl carbon atom of a (.pi.-allyl)platinum complexKouichi Ohe, Hideki Matsuda, Tsumoru Morimoto, Sensuke Ogoshi, Naoto Chatani, and Shinji MuraiCite this: J. Am. Chem. Soc. 1994, 116, 9, 4125–4126Publication Date (Print):May 1, 1994Publication History Published online1 May 2002Published inissue 1 May 1994https://pubs.acs.org/doi/10.1021/ja00088a077https://doi.org/10.1021/ja00088a077research-articleACS Publicati

The reaction of cis vicinal acetylethynylcyclopropanes 1 with a catalytic amount of M(CO)5(THF) (M = Cr or W) in the presence of Et3N at room temperature gave ortho-substituted phenols 7 in good yields as valence isomerized products. In the absence of Et3N the reactions did not work at all. The reaction of a cyclopropane having an ester or an amide instead of an acetyl moiety with M(CO)5(THF) did not take place, whereas an ethynylvinylcyclopropane gave a mixture of 1- and 2-substituted 1,3,5-cyc

A transition metal catalyst can trigger the cycloaromatization of an enediyne. A coordinatively unsaturated rhodium complex catalyzes the cyclization of the acyclic enediyne 1 to produce 3. The cyclization, which is similar to the Myers reaction, proceeds via a vinylidene–rhodium intermediate and the 1,4-organorhodium diradical 2. Rh = [RhCl(iPr3P)2].

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSodium arenetellurolate-catalyzed selective conversion of nitro aromatics to aromatic azoxy or azo compounds and its application for facile preparation of 3,3'- and 4,4'-bis[.beta.-(aryltelluro)vinyl]azobenzenes from (3- and 4-nitrophenyl)acetylenesKouichi Ohe, Sakae Uemura, Nobuyuki Sugita, Hideki Masuda, and Toru TagaCite this: J. Org. Chem. 1989, 54, 17, 4169–4174Publication Date (Print):August 1, 1989Publication History Published online1 May 2002Pu

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPalladium-catalyzed reaction of 5-methylene-1,3-dioxolan-2-ones. A new access to and reactivity of oxatrimethylenemethane-palladiumKouichi Ohe, Hideki Matsuda, Toshihisa Ishihara, Sensuke Ogoshi, Naoto Chatani, and Shinji MuraiCite this: J. Org. Chem. 1993, 58, 5, 1173–1177Publication Date (Print):February 1, 1993Publication History Published online1 May 2002Published inissue 1 February 1993https://pubs.acs.org/doi/10.1021/jo00057a033https://doi.org/10

The reaction of conjugated enyne−carbonyl compounds such as 1-(alkoxycarbonyl)-2-ethynylcycloalkenes and 1-carbamoyl-2-ethynylcycloalkenes with Mo(CO)5·NEt3 and W(CO)5·THF gave the corresponding 6-alkoxy- and 6-amino-2H-pyranylidene−molybdenum and −tungsten complexes, respectively. The cycloisomerization reaction of the conjugated vinylidene−ene−carbonyl complexes generated from 1-(alkoxycarbonyl)- or 1-carbamoyl-2-ethynylcycloalkenes and metals is a key route to these Fischer-type oxacarbene co

The ruthenium-catalyzed isomerization of diynes and triynes involving propargyl carboxylate moieties affords dienynes and dienediynes, respectively. The [1,n]-metallotropic shift (n = 3, 5) (carbene walk) of in situ generated alkynyl carbene complexes has been proposed for the catalytic isomerization reaction.