Dataset Information

Hybrids of salicylalkylamides and Mannich bases: control of the amide conformation by hydrogen bonding in solution and in the solid state.

ABSTRACT: 3-Aminomethylation of salicylalkylamides afforded hybrids with a Mannich base. In addition, it triggered the rotation of the amide bond. The observed conformational switch is driven by strong intramolecular hydrogen bonding between the Mannich base and phenolic group. Crystal structure analysis reveals the stabilization of the hybrid molecules by double hydrogen bonding of the phenolic OH, which acts as an acceptor and donor simultaneously. The molecules contain an amide site and a Mannich base site in an orthogonal spatial arrangement. The intramolecular hydrogen bonds are persistent in a nonpolar solvent (e.g., chloroform). The conformational change can be reversed upon protection or protonation of the Mannich base nitrogen.

SUBMITTER: Dank C

PROVIDER: S-EPMC6272445 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Hybrids of salicylalkylamides and Mannich bases: control of the amide conformation by hydrogen bonding in solution and in the solid state.

Dank Christian C Kirchknopf Barbara B Mastalir Matthias M Kählig Hanspeter H Felsinger Susanne S Roller Alexander A Arion Vladimir B VB Gstach Hubert H

Molecules (Basel, Switzerland) 20150120 1

3-Aminomethylation of salicylalkylamides afforded hybrids with a Mannich base. In addition, it triggered the rotation of the amide bond. The observed conformational switch is driven by strong intramolecular hydrogen bonding between the Mannich base and phenolic group. Crystal structure analysis reveals the stabilization of the hybrid molecules by double hydrogen bonding of the phenolic OH, which acts as an acceptor and donor simultaneously. The molecules contain an amide site and a Mannich base ...[more]

PMID: 25608856

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Dataset Information

Hybrids of salicylalkylamides and Mannich bases: control of the amide conformation by hydrogen bonding in solution and in the solid state.

Publications

Hybrids of salicylalkylamides and Mannich bases: control of the amide conformation by hydrogen bonding in solution and in the solid state.

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