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Asymmetric hydrosilylation of ketones catalyzed by complexes formed from trans-diaminocyclohexane-based diamines and diethylzinc.

ABSTRACT:

Abstract

Chiral acyclic and macrocyclic amines derived from trans-1,2-diaminocyclohexane in complexes with diethylzinc efficiently catalyze asymmetric hydrosilylation of aryl-alkyl and aryl-aryl ketones with enantiomeric excess of the product up to 86 %. A trianglamine ligand with a cyclic structure or the presence of an additional coordinating group increases the enantioselectivity of the reaction, in comparison with catalysis by a simple acyclic N,N'-dibenzyl-1,2-diaminocyclohexane ligand. In addition, the effect of the asymmetric activation of the catalyst by a variety of alcohols and diols is studied.

Graphical abstract

SUBMITTER: Gajewy J

PROVIDER: S-EPMC4494764 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Asymmetric hydrosilylation of ketones catalyzed by complexes formed from <i>trans</i>-diaminocyclohexane-based diamines and diethylzinc.

Gajewy Jadwiga J Gawronski Jacek J Kwit Marcin M

Monatshefte fur chemie 20120418 7

<h4>Abstract</h4>Chiral acyclic and macrocyclic amines derived from <i>trans</i>-1,2-diaminocyclohexane in complexes with diethylzinc efficiently catalyze asymmetric hydrosilylation of aryl-alkyl and aryl-aryl ketones with enantiomeric excess of the product up to 86 %. A trianglamine ligand with a cyclic structure or the presence of an additional coordinating group increases the enantioselectivity of the reaction, in comparison with catalysis by a simple acyclic <i>N</i>,<i>N</i>'-dibenzyl-1,2-d ...[more]

PMID: 26166868

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