title: Hydrogen bonding in nitroaniline analogues: hydrogen-bonded sheets in 2-amino-4,6-dimethoxy-5-nitropyrimidine and pi-stacked hydrogen-bonded sheets in 4-amino-2,6-dimethoxy-5-nitropyrimidine.
abstract: In 2-amino-4,6-dimethoxy-5-nitropyrimidine, C(6)H(8)N(4)O(4), the molecules are linked by one N-H...N and one N-H...O hydrogen bond to form sheets built from alternating R(2)(2)(8) and R(6)(6)(32) rings. In isomeric 4-amino-2,6-dimethoxy-5-nitropyrimidine, C(6)H(8)N(4)O(4), which crystallizes with Z' = 2 in P-1, the two independent molecules are linked into a dimer by two independent N-H...N hydrogen bonds. These dimers are linked into sheets by a combination of two-centre C-H...O and three-centre C-H...(O)(2) hydrogen bonds, and the sheets are further linked by two independent aromatic pi-pi-stacking interactions to form a three-dimensional structure.
authors.affiliation: School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, Scotland. cg@st-andrews.ac.uk
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell
authors.forename: John N
authors.initials: JN
authors.lastname: Low
authors.forename: Manuel
authors.initials: M
authors.lastname: Melguizo
authors.forename: Antonio
authors.initials: A
authors.lastname: Quesada