Synthesis of 5- to 8-membered cyclic carbonates from diols and CO₂:A one-step, atmospheric pressure and ambient temperature procedure

Abstract

6-, 7- and 8-membered ring cyclic carbonates are of particular interest as monomers for ring-opening polymerisation towards more sustainable polymers. They are traditionally synthesised from diols and phosgene derivatives, and while alternative CO2 methods exist to make 5- and 6-membered cyclic carbonates, there is no report of the synthesis of 7- and 8-membered cyclic carbonates made directly from CO2. Herein we report an efficient one-pot synthesis of cyclic carbonates which uses diols, CO2, tosyl chloride and mild bases (NEt3 or TMP), under ambient temperature and 1 atm of CO2 pressure. Fifteen cyclic carbonates were synthesised, including twelve known monomers, and the first examples of 7- and 8-membered cyclic carbonates made using CO2.</p