Piperazine-2,5-dione-oxalic acid-water (1/1/2) and a redetermination of piperazine-2,5-dione, both at 120 K: hydrogen-bonded sheets containing multiple ring types.
In piperazine-2,5-dione-oxalic acid-water (1/1/2), C4H6N2O2.C2H2O4.2H2O, both organic components lie across inversion centres in space group P-1. The molecules are linked by N-H...O and by both two-centre O-H...O and three-centre O-H...(O)2 hydrogen bonds into sheets built from R(1)(2)(5), R(2)(2)(8), R(4)(4)(8) and R(5)(4)(15) rings. In piperazine-2,5-dione, C4H6N2O2, where the molecules lie across centres of inversion in space group P2(1)/c, the molecules are linked by paired N-H...O hydrogen bonds into ribbons of centrosymmetric R(2)(2)(8) rings, which are further linked into sheets by C-H...O hydrogen bonds, generating R(4)(3)(14) rings between the ribbons.
Sarangarajan
Thanjavur Ramabhadran
TR
School of Chemical and Biotechnology, Shanmugha Arts, Science, Technology and Research Academy (SASTRA), Tirumalaisamudram, Thanjavur 623 106, India.
Panchanatheswaran
Krishnaswamy
K
Low
John N
JN
Glidewell
Christopher
C