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Chalcogen Bonding Catalysis of a Nitro-Michael Reaction.

ABSTRACT: Chalcogen bonding is the non-covalent interaction between Lewis acidic chalcogen substituents and Lewis bases. Herein, we present the first application of dicationic tellurium-based chalcogen bond donors in the nitro-Michael reaction between trans-?-nitrostyrene and indoles. This also constitutes the first activation of nitro derivatives by chalcogen bonding (and halogen bonding). The catalysts showed rate accelerations of more than a factor of 300 compared to strongly Lewis acidic hydrogen bond donors. Several comparison experiments, titrations, and DFT calculations support a chalcogen-bonding-based mode of activation of ?-nitrostyrene.

SUBMITTER: Wonner P

PROVIDER: S-EPMC6899570 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Chalcogen Bonding Catalysis of a Nitro-Michael Reaction.

Wonner Patrick P Dreger Alexander A Vogel Lukas L Engelage Elric E Huber Stefan M SM

Angewandte Chemie (International ed. in English) 20191023 47

Chalcogen bonding is the non-covalent interaction between Lewis acidic chalcogen substituents and Lewis bases. Herein, we present the first application of dicationic tellurium-based chalcogen bond donors in the nitro-Michael reaction between trans-β-nitrostyrene and indoles. This also constitutes the first activation of nitro derivatives by chalcogen bonding (and halogen bonding). The catalysts showed rate accelerations of more than a factor of 300 compared to strongly Lewis acidic hydrogen bond ...[more]

PMID: 31535789

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