Zn(ii), Cd(ii) and Cu(ii) complexes of 2,5-bis{N-(2,6-diisopropylphenyl)iminomethyl}pyrrole: synthesis, structures and their high catalytic activity for efficient cyclic carbonate synthesis.Electronic supplementary information (ESI) available: Crystallographic data and structures of complexes 3a, 3b, 5a and 5b, spectra of all complexes and cyclic carbonates. CCDC 874343 (3b), 885290 (5a) and CCDC 885291 (5b). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2

The syntheses of Zn( ii ), Cd( ii ) and Cu( ii ) complexes of 2,5-bis{ N -(2,6-diisopropylphenyl)iminomethyl}pyrrole (DIP 2 pyr)H 1 and their catalytic activities in CO 2 fixation are reported. The structures of these complexes were characterized by IR, 1 H, 13 C NMR and single crystal X-ray diffraction techniques. The catalytic activities of these complexes for the cycloaddition of CO 2 to an epoxide under one atmosphere of pressure and mild temperature conditions to yield cyclic carbonate have been studied. Among the four complexes synthesized, the Zn( ii ) and Cu( ii ) complexes were found to be versatile whereas the Cu( ii ) complex was more selective in the conversion. They were highly effective for the conversion of monosubstituted terminal epoxides, disubstituted terminal and internal epoxides to their corresponding cyclic carbonates with good to high yields. Mono and disubstituted epoxides can be converted efficiently into cyclic carbonate using Zn( ii ), Cd( ii ) or Cu( ii ) complexes of 2,5-bis{ N -(2,6-diisopropylphenyl)iminomethyl}pyrrole as a catalyst in the presence of TBAB at 1 atm of CO 2 .