reaction occurred on treatment of 2-(alkynyl)aryl isocyanates with amides in the presence of a palladium(0)/diphosphine catalyst to stereoselectively form 3-(amidoalkylidene)oxindoles. A carbon−nitrogen bond as well as a carbon−carbon bond were simultaneously introduced onto the alkyne moiety to construct an oxindole skeleton with stereoselective placement of the amino substituent cis to the carbonyl group
A Bimetallic Catalyst and Dual Role Catalyst: Synthesis of <i>N</i>-(Alkoxycarbonyl)indoles from 2-(Alkynyl)phenylisocyanates
作者:Shin Kamijo、Yoshinori Yamamoto
DOI:10.1021/jo034254p
日期:2003.6.1
step proceeds with a cooperative catalytic activity of Pd and Cu. On the other hand, N-(alkoxycarbonyl)indoles are produced via the reaction of 2-(alkynyl)phenylisocyanates and alcohols under a catalytic amount of Na(2)PdCl(4) (5 mol %) or PtCl(2) (5 mol %). Pd(II) or Pt(II) catalyst exhibits dual roles; it acts as a Lewis acid to accelerate the addition of alcohols to isocyanates and as a typical transition-metal
Stereoselective Synthesis of 3-Alkylideneoxindoles by Rhodium-Catalyzed Cyclization Reaction of 2-Alkynylaryl Isocyanates with Aryl- and Alkenylboronic Acids
The rhodium-catalyzed cyclization reaction of 2-alkynylaryl isocyanates with aryl- and alkenylboronic acids furnishes 3-alkylideneoxindoles in a stereoselective manner. The reaction allows arrangement of various substituents on the exocyclic double bond and aromatic ring with wide functional tolerance.
Stereoselective Synthesis of 3-(1-Cyanoalkylidene)oxindoles by Palladium-catalyzed Cyclization Reaction of 2-(Alkynyl)aryl Isocyanates with Copper(I) Cyanide
A palladium-catalyzed cyclization reaction of 2-(alkynyl)-aryl isocyanates with copper(I) cyanide provides an efficient method for the stereoselective synthesis of (Z)-configured 3-(1-cyanoalkylidene)oxindoles.