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Catalytic Carbon-Chlorine Bond Activation by Selenium-Based Chalcogen Bond Donors.

ABSTRACT: Chalcogen bonding is a noncovalent interaction based on electrophilic chalcogen substituents, which shares many similarities with the more well-known hydrogen and halogen bonding. Herein, the first application of selenium-based chalcogen bond donors in organocatalysis is described. Cationic bifunctionalized organoselenium compounds activate the carbon-chlorine bond of 1-chloroisochroman in a benchmark reaction. While imidazolium-based derivatives showed no noticeable activation, benzimidazolium backbones yielded potent catalysts. In all cases, syn-isomers were markedly more active, presumably due to bidentate coordination, which was confirmed by DFT calculations. Comparison experiments with the corresponding non-selenated as well as the non-cationic reference compounds clearly indicate that the catalytic activity can be ascribed to chalcogen bonding. The rate acceleration by the catalyst-compared to the non-selenated derivative-was about 10 fold.

SUBMITTER: Wonner P

PROVIDER: S-EPMC5725716 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Catalytic Carbon-Chlorine Bond Activation by Selenium-Based Chalcogen Bond Donors.

Wonner Patrick P Vogel Lukas L Kniep Florian F Huber Stefan M SM

Chemistry (Weinheim an der Bergstrasse, Germany) 20171114 67

Chalcogen bonding is a noncovalent interaction based on electrophilic chalcogen substituents, which shares many similarities with the more well-known hydrogen and halogen bonding. Herein, the first application of selenium-based chalcogen bond donors in organocatalysis is described. Cationic bifunctionalized organoselenium compounds activate the carbon-chlorine bond of 1-chloroisochroman in a benchmark reaction. While imidazolium-based derivatives showed no noticeable activation, benzimidazolium ...[more]

PMID: 29057533

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