Abstract

A highly inexpensive, and operationally simple seralite SRC-120 (strongly acidic cation exchange resin) catalyzed synthesis of 3,3′-bis(indolyl)methanes (BIMs) from indoles and low/high boiling point carbonyl compounds under solvent-free condition is reported. Synthesis of BIMs with low boiling point carbonyls at room temperature takes prolonged reaction time and give low yields at high temperature. The reported method overcomes these limitations and works remarkably well with low/high boiling point aldehydes/ketones in shorter reaction times (5–10 min) under microwave irradiation conditions and provides moderate to excellent yields (65–94%). Moreover, the recyclability of the catalyst for at least five times without notable loss in activity makes the whole process attractive and green protocol.

摘要

在无溶剂条件下，由吲哚和低/高沸点羰基化合物合成的3,3'-双（吲哚基）甲烷（BIM）的合成反应非常便宜，并且操作简单，是一种Seralite SRC-120（强酸性阳离子交换树脂）。报告。在室温下合成具有低沸点羰基的BIM会延长反应时间，并且在高温下产率较低。报道的方法克服了这些限制，并且在微波辐射条件下以较短/较短的反应时间（5-10分钟）与低/高沸点醛/酮一起使用时效果显着，并提供中等至极好的收率（65-94％）。而且，催化剂至少可循环使用五次而活性没有明显损失，这使整个过程具有吸引力且绿色环保。