Crystal structure and Hirshfeld analysis of 3′-bromo-4-methylchalcone and 3′-cyano-4-methylchalcone

Abstract

Two crystal structures of chalcones, or 1,3-diarylprop-2-en-1-ones, are presented; both contain a methyl substitution on the 3-Ring, but differ on the 1-Ring, bromo versus cyano. The compounds are 3′-bromo-4-methylchalcone [systematic name: 1-(2-bromophenyl)-3-(4-methylphenyl)prop-2-en-1-one], C16H13BrO, and 3′-cyano-4-methylchalcone {systematic name: 2-[3-(4-methylphenyl)prop-2-enoyl]benzonitrile}, C17H13NO. Both chalcones meaningfully add to the large dataset of chalcone structures. The crystal structure of 3′-cyano-4-methylchalcone exhibits close contacts with the cyano nitrogen that do not appear in previously reported disubstituted cyanochalcones, namely interactions between the cyano nitrogen atom and a ring hydrogen atom as well as a methyl hydrogen atom. The structure of 3′-bromo-4-methylchalcone exhibits a type I halogen bond, similar to that found in a previously reported structure for 4-bromo-3′-methylchalcone.

Keywords

• crystal structure
• chalcone
• bromo
• cyano
• halogen bond
• π stacking
• edge-to-face