Open AccessSupramolecular structures of five 5‐(arylmethylene)‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐triones: isolated molecules, hydrogen‐bonded chains and chains of fused hydrogen‐bonded rings
Author(s) -
Rezende Marcos C.,
Dominguez Moisés,
Wardell James L.,
Skakle Janet M. S.,
Low John N.,
Glidewell Christopher
Publication year - 2005
Publication title -
acta crystallographica section c
Language(s) - English
Resource type - Journals
eISSN - 1600-5759
pISSN - 0108-2701
DOI - 10.1107/s0108270105008498
Subject(s) - pyrimidine , chemistry , hydrogen bond , supramolecular chemistry , molecule , stereochemistry , crystallography , medicinal chemistry , crystal structure , organic chemistry
In each of the five title compounds, namely 5‐benzylidene‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐trione, C 13 H 12 N 2 O 3 , (I), 5‐(3‐methoxybenzylidene)‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐trione, C 14 H 14 N 2 O 4 , (II), 5‐(4‐methoxybenzylidene)‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐trione, C 14 H 14 N 2 O 4 , (III), 5‐[4‐(dimethylamino)benzylidene]‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐trione, C 15 H 17 N 3 O 3 , (IV), and 5‐(3,5‐di‐ tert ‐butyl‐4‐hydroxybenzylidene)‐1,3‐dimethylpyrimidine‐2,4,6(1 H ,3 H ,5 H )‐trione, C 21 H 28 N 2 O 4 , (V), which crystallizes with Z ′ = 2 in P , there is a very wide C—C—C angle at the methine C atom linking the two rings, ranging from 137.1 (2)° in (I) to 139.14 (14)° in (III). There is evidence for intramolecular charge separation in (IV) and, to a lesser degree, in (III). The molecules of (I)–(III) are linked by pairs of C—H⋯O hydrogen bonds into chains of edge‐fused rings, with alternating R 2 2 (14) and R 2 2 (16) rings in (I), alternating R 2 2 (14) and R 4 4 (20) rings in (II), with two types of R 2 2 (16) rings alternating in (III). The molecules in (IV) are linked by a single C—H⋯O hydrogen bond into simple C (8) chains, but there are no direction‐specific intermolecular interactions in (V).