Hydroselenation of alkynes using NaBH4/BMIMBF4: easy access to vinyl selenides
作者:Eder J. Lenardão、Luiz G. Dutra、Maiara T. Saraiva、Raquel G. Jacob、Gelson Perin
DOI:10.1016/j.tetlet.2007.09.042
日期:2007.11
A general and easy method for the synthesis of several vinyl selenides using NaBH4 and BMIMBF4 as a recyclable solvent is described. This efficient and improved method furnishes the corresponding vinyl chalcogenides preferentially with Z configuration. We also observed that when the same protocol was applied to phenyl acetylene, (E)-bis-phenylseleno styrene was obtained in good yield and with high selectivity. (c) 2007 Elsevier Ltd. All rights reserved.
Addition of chalcogenolate anions to terminal alkynes using microwave and solvent-free conditions: easy access to bis-organochalcogen alkenes
作者:Gelson Perin、Raquel G. Jacob、Luiz G. Dutra、Francisco de Azambuja、Greice F.F. dos Santos、Eder J. Lenardão
DOI:10.1016/j.tetlet.2005.11.158
日期:2006.2
We present here the reaction of diphenyl dichalcogenides (Se and Te) with propargyl alcohols using alumina supported sodium borohydride under solvent-free conditions. This efficient and improved method is general and furnishes the corresponding vinyl chalcogenide preferentially with a Z configuration. We also observed that when the same protocol was applied to phenyl acetylene, the (E)-bis-organochalcogen alkenes were obtained in good yields and high selectivity. The use of MW irradiation facilitates the procedure and accelerates the reaction. (c) 2005 Elsevier Ltd. All rights reserved.
Cerium(III)-Mediated Efficient and Stereoselective Hydrochalcogenation of Terminal Alkynes
Vinylic chalcogenides were synthesized stereospecifically by hydrochalcogenation of propargylic amines or alcohols mediated by cerium(III) chloride. The products were obtained in good yields and with high regio- and stereoselectivities. cerium chloride - vinylic chalcogenides - hydrochalcogenation - selenium - tellurium