SYNTHESIS AND CRYSTAL STRUCTURE OF A 1:1:1 ADDUCT OF N,N'-DI(m-TOLYL)PIPERAZINE N,N'-DIOXIDE, ACETIC ACID AND WATER

Article abstract of DOI:10.1016/0022-2860(89)80126-7

A 1:1:1 adduct of N,N'-di(m-tolyl)piperazine N,N'-dioxide, acetic acid, and water has been synthesized.The crystals are orthorombic, space group Pca2₁, (No. 29), with a=15.712(3), b=6.018(1), c=19.940(5) Angstroem, V=1885.4(7) <*>, Z=4 and D_c=1.290 g cm^-3.The structure has been refined to R=0.076 for 1885 observed Mo Kα reflections.The piperazine ring in the N,N'-dioxide molecule takes the chair form, with two N-O bonds oriented axially in a trans configuration.Proton transfer from the acetic acid molecule to the N,N'-dioxide molecule was found in the adduct.Strong hydrogen bonds, each involving a proton and the oxygen atoms of two N-oxide groups from adjacent N,N'-dioxide molecules, connect the latter into a zigzag chain along the b axis.The acetate ions and the water molecules are alternately linked by hydrogen bonds to form an infinite chain along the b axis.The crystal structure is built up from a lateral stacking of these two types of chain.The length of the novel N-O...H+...O-N hydrogen bond is 2.454(6) Angstroem.