Zinc grafted to magnetic nanostarch for cyclic carbonate synthesis from propargylic alcohols and CO2 at room temperature

A novel, cost effective and magnetically separable nanocrystalline starch zinc catalyst was developed for the synthesis of alpha-alkylidene cyclic carbonates from propargylic alcohols and CO2 at room temperature under solvent-free conditions. The synthesized nanocomposite along with triethylamine played excellent synergistic roles in activating both CO2 and propargylic alcohols and afforded desired products in moderate to excellent yields. The salient features such as the use of renewable, inexpensive support matrix, facile separation of the catalyst by an external magnet, mild reaction conditions, excellent product yields and heterogeneous nature of the catalyst without any detectable leaching make the developed methodology promising for the synthesis of a-alkylidene cyclic carbonates.