Conformational control of N-methyl-N,N'-diacylhydrazines by noncovalent carbon bonding in solution

Chem Commun (Camb). 2020 May 4;56(36):4874-4877. doi: 10.1039/d0cc00943a. Epub 2020 Apr 7.

Abstract

In recent years, some X-ray structural and computational evidence has emerged for noncovalent carbon bonding (C-bond). However, evidence of C-bonds in solution is limited. Herein, from the conformational analyses of strategically designed N-methyl-N,N'-diacylhydrazines, we for the first time show that C-bonds can be modulated to control the conformational preferences of small molecules in solution. We show that unusual N(amide)C-X noncovalent carbon bonding interactions stabilize the trans-cis (t-c) amide bond rotamers of N-methyl-N,N'-diacylhydrazines over the expected trans-trans (t-t) rotamers.