Abstract

An environmentally viable, green and efficient protocol for the synthesis of polyhydroquinolines using sulfated polyborate catalyst have been developed by Hantzsch four-component condensation between aromatic aldehydes, dimedone, ammonium acetate and ethylacetoacetate or ethylcyanoacetate at 100 °C under solvent-free condition. The sulfated polyborate catalyst is characterized by FT-IR, XRD, SEM and EDAX techniques. The noticeable features of this methodology are mild Brønsted acidic nature of the catalyst, good to excellent product yields (85–94%), short reaction time (18–30 min), solvent-free condition, operational simplicity and applicability to a wide range of substrates (29 examples).

Graphic Abstract

This work deals with sulfated polyborate catalysed green and efficient solvent-free synthesis of polyhydroquinolines.

中文翻译：

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硫酸化多硼酸盐作为一种生态兼容的固体酸催化剂，可高效，轻松地无溶剂合成聚氢喹啉

摘要

Hantzsch在无溶剂条件下于100°C下通过芳族醛，二甲酮，乙酸铵和乙酰乙酸乙酯或氰基乙酸乙酯之间的四组分缩合反应，开发了一种使用硫酸化多硼酸酯催化剂合成多氢喹啉的环保可行，绿色高效的方法。硫酸化多硼酸盐催化剂通过FT-IR，XRD，SEM和EDAX技术表征。该方法的显着特点是催化剂具有温和的布朗斯台德酸性性质，良好至优异的产品收率（85–94％），较短的反应时间（18–30分钟），无溶剂条件，操作简便且适用范围广基板数量（29个示例）。

图形摘要

这项工作涉及硫酸化的多硼酸酯催化的绿色和高效的无溶剂合成多氢喹啉。