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Comparing kinetic profiles between bifunctional and binary type of Zn(salen)-based catalysts for organic carbonate formation.

ABSTRACT: Zn(salen) complexes have been employed as active catalysts for the formation of cyclic carbonates from epoxides and CO2. A series of kinetic experiments was carried out to obtain information about the mechanism for this process catalyzed by these complexes and in particular about the order-dependence in catalyst. A comparative analysis was done between the binary catalyst system Zn(salphen)/NBu4I and a bifunctional system Zn(salpyr)·MeI with a built-in nucleophile. The latter system demonstrates an apparent second-order dependence on the bifunctional catalyst concentration and thus follows a different, bimetallic mechanism as opposed to the binary catalyst that is connected with a first-order dependence on the catalyst concentration and a monometallic mechanism.

SUBMITTER: Martin C

PROVIDER: S-EPMC4143085 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Comparing kinetic profiles between bifunctional and binary type of Zn(salen)-based catalysts for organic carbonate formation.

Martín Carmen C Kleij Arjan W AW

Beilstein journal of organic chemistry 20140808

Zn(salen) complexes have been employed as active catalysts for the formation of cyclic carbonates from epoxides and CO2. A series of kinetic experiments was carried out to obtain information about the mechanism for this process catalyzed by these complexes and in particular about the order-dependence in catalyst. A comparative analysis was done between the binary catalyst system Zn(salphen)/NBu4I and a bifunctional system Zn(salpyr)·MeI with a built-in nucleophile. The latter system demonstrates ...[more]

PMID: 25161742

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