Baker’s yeast as an efficient biocatalyst for regioselective 1,4-conjugate addition of indoles to nitroolefins in aqueous medium
作者:Ananda Mane、Trushant Lohar、Rajashri Salunkhe
DOI:10.1016/j.tetlet.2016.04.057
日期:2016.6
The 1,4-conjugate addition of indoles to nitroolefins was efficiently carried out in aqueous media using baker’s yeast as a biocatalyst at room temperature. The merits of the present method are operational simplicity, easy workup, utilization of an inexpensive catalyst, free from hazardous organic solvents and good yields of products. The generality of this method was demonstrated by synthesizing an
Michael addition of indoles to beta-nitrostyrenes is reported using HY zeolite as catalyst under mild reaction conditions. This methodology allows the synthesis of various indole derivatives in good to high yields at 50 C under solvent-free conditions. The short reaction time and achieving high yield of the desired products are the main advantages of the present work. The catalyst can be easily recovered and reused for six successive runs without considerable changes in yields. This Michael addition catalyzed by HY zeolite is operationally simple and can be considered as a greener protocol as it avoids the use of corrosive acids and toxic reagents. (C) 2014 Elsevier Ltd. All rights reserved.
Boric Acid–Mediated Mild and Efficient Friedel–Crafts Alkylation of Indoles with Nitro Styrenes
作者:H. M. Meshram、N. Nageswara Rao、G. Santosh Kumar
DOI:10.1080/00397910903457316
日期:2010.11.3
An efficient method has been developed for the synthesis of indole 3-derivatives by the Friedel–Crafts alkylation of indole with nitroolefins in presence of boric acid in aqueous medium.