Tuning of Regioselectivity in the Coupling Reaction Involving Allenic/Propargylic Palladium Species
作者:Shengming Ma、Aibin Zhang
DOI:10.1021/jo0111098
日期:2002.4.1
Two different types of coupling patterns for the Pd(0)-catalyzed coupling reaction of allenic/propargylic zinc reagents with organic halides or propargylic carbonates (acetate) with the corresponding organometallicreagents were observed. After studying the controlling factors on the regioselectivity of this reaction, we demonstrated that the steric hindrance of both reactants and the types of organic
The palladium catalyzed cross-coupling reaction of trialky](indol-2-yl)borates with prop-2-ynyl carbonates was developed for the preparation of 2-allenylindole derivatives. When the reaction of indolyl-borates with tert-prop-2-ynyl carbonates was carried out. 2-allenylindoles were obtained solely. Otherwise, indolylborates reacted with sec-prop-2-ynyl carbonates, giving rise to 2-allenylindoles and/or 3-(prop-2-ynyl)indoles depending on the catalyst used. (C) 1998 Elsevier Science Ltd. All rights reserved.
Ruthenium-Catalyzed <i>S</i>-Propargylation of Thiols Enables the Rapid Synthesis of Propargylic Sulfides
A new and highly efficient catalytic system based on CpRuClL2 is proposed for the S-propargylation of thiols by propargylic carbonates under neutral conditions, in which specific requirements inherent to the different reactivities of aliphatic and aromatic thiols are achieved by tuning both the nature of the ancillary ligand L and the experimental conditions.
Palladium-Catalyzed Reductive Homocoupling Reaction of 3-Silylpropargyl Carbonates. New Entry into Allene-Yne Compounds