Masao Hirano

Amide-Directed Alkenylation of sp2 C−H Bonds Catalyzed by a Cationic Rh(I)/BIPHEP Complex Under Mild Conditions: Dramatic Rate Acceleration by a 1-Pyrrolidinecarbonyl Group

A cationic rhodium(I)/BIPHEP complex catalyzes amide-directed regioselective alkenylations of olefinic or aromatic sp(2) C-H bonds in good yields under mild reaction conditions. The use of a 1-pyrrolidinecarbonyl group as a directing group dramatically accelerates the reaction.

Convergent and rapid assembly of substituted 2-pyridones through formation of N-alkenyl alkynylamides followed by gold-catalyzed cycloisomerization.

A new method for the convergent and rapid assembly of substituted 2-pyridones was developed through the formation of N-alkenyl alkynylamides (amide-linked 1,5-enynes) by N-acylation of imines with alkynoyl chlorides and the subsequent cationic Au(I)/PPh 3-catalyzed cycloisomerization.

Liquid Enol Ethers and Acetates as Gaseous Alkyne Equivalents in Rh-Catalyzed Chemo- and Regioselective Formal Cross-Alkyne Cyclotrimerization

A cationic rhodium(I)/rac-BINAP complex catalyzes chemo- and regioselective formal cross-cyclotrimerizations of alkynes with enol ethers or acetates. Commercially available and cheap liquid enol ethers and acetates could be used as convenient gaseous alkyne equivalents in the present rhodium catalyses.

Rhodium-catalyzed regio- and stereoselective codimerization of alkenes and electron-deficient internal alkynes leading to 1,3-dienes.

A cationic rhodium(I)/H(8)-BINAP complex catalyzes codimerization of alkenes bearing no alpha-hydrogen and electron-deficient internal alkynes, leading to 1,3-dienes in good yields with moderate to excellent regio- and stereoselectivity. The same complex also catalyzes codimerization of an acrylate and phenyl-substituted electron-rich internal alkynes, leading to 1,3-dienes.

Manganese(III)-Catalysed Oxidation of Sulphides with Sodium Chlorite in an Aprotic Solvent in the Presence of Alumina

Abstract A wide variety of sulphides can be readily converted to the corresponding sulphoxides in good to excellent yields by treatment with a combination of sodium chlorite, (salen)manganese(III) complex, and chromatographic alumina in dichloromethane under mild and neutral conditions.

Rhodium-catalyzed highly enantio- and diastereoselective cotrimerization of alkenes and dialkyl acetylenedicarboxylates leading to furylcyclopropanes.

A cationic rhodium(I)/Segphos or H(8)-BINAP complex catalyzes the unprecedented cotrimerization of commercially available monoenes and dialkyl acetylenedicarboxylates, leading to functionalized furylcyclopropanes with excellent enantioselectivity and perfect diastereoselectivity.

A New Route to Substituted Phenols by Cationic Rhodium(I)/BINAP Complex-Catalyzed Decarboxylative [2 + 2 + 2] Cycloaddition

A new route to substituted phenols has been developed by cationic rhodium(I)/BINAP complex-catalyzed decarboxylative [2 + 2 + 2] cycloadditions of 1,6- and 1,7-diynes with commercially available vinylene carbonate.

Highly Enantioselective Construction of Axial Chirality by Palladium-Catalyzed Cycloisomerization of N-Alkenyl Arylethynylamides

A cationic palladium(II)/(S)-xyl-Segphos complex catalyzes enantioselective cycloisomerizations of N-alkenyl arylethynylamides leading to axially chiral 4-aryl-2-pyridones in high yields with high ee values. The present catalysis represents the first enantioselective construction of axial chirality by the transition-metal-catalyzed cycloisomerization.

An Environmentally Friendly Oxidation of Thiols to Disulfides by Calcium Hypochlorite and Montmorillonite K10 in Hexane

Abstract — Aromatic, aliphatic, and alicyclic thiols can be readily oxidized to the disulfides quantitatively by calcium hypochlorite and moist Montmorillonite K10 under mild and neutral conditions.

α-Chlorination of Ketones with Sodium Chlorite, Mn(acac)3, and Alumina in Dichloromethane

Chlorination of a variety of aliphatic, alicyclic, and aromatic ketones with a reagent combination of NaClO2 and Mn(acac)3 catalyst can be readily performed in dichloromethane to afford α-chloroket...