Boosting the catalytic performance of organic salts for the fast and selective synthesis of α‐alkylidene cyclic carbonates from CO2 and propargylic alcohols.

Bruno Grignard; Charlene Ngassamtounzoua; Sandro Gennen; Bernard Gilbert; Raphael Mereau; Christine Jerome; Thierry Tassaing; Christophe Detrembleur

Index: 10.1002/cctc.201800063

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Abstract

The synthesis of α‐alkylidene cyclic carbonates (αCCs) by carboxylative coupling of CO2 with propargylic alcohols is receiving increasing interest but requires the use of catalysts that are most often added in large quantity and/or are lacking of selectivity. Herein, we describe that the fine‐tuning of the structure of organocatalysts of the ammonium‐type enables to identify the important structural parameters that dictate their catalytic performance. Tetrabutylammonium oxalate revealed to be one of the most attractive organocatalysts with a remarkable fast, complete and selective production of αCCs at low catalyst loading (2.5 mol%) under solvent free‐conditions. This study clearly opens new avenues for the facile and selective synthesis of libraries of αCCs from CO2 and propargylic alcohol by using simple organocatalysts.