Noncentrosymmetry in new 2-methylpiperazinediium hexaaquazinc(II) bis(sulfate).

Naïli, Houcine

Two new noncentrosymmetric polar zinc sulfates have been synthesized by slow evaporation through the use of enantiomorphically pure sources of either (R)-2-methylpiperazine or (S)-2-methylpiperazine. A centrosymmetric analog was also prepared using a racemic source of the amine. The 3-D structure networks for these compounds consist of isolated [Zn(H2O)6]2 , [C5H14N2]2 , and linked by hydrogen bonds. The use of racemic 2-methylpiperazine results in crystallographic disorder of the amines and creation of inversion centers, while using a single enantiomer destroys the inversion symmetry and orders of the amines. These structures were determined using single-crystal X-ray diffraction, infrared spectroscopy, and thermal analyses. Crystal data are as follows: [C5H14N2][Zn(H2O)6](SO4)2 (1), a = 6.5988(1) Å, b = 10.9613(2) Å, c = 12.5479(2) Å, β = 101.385(1)°, V = 889.75(3) Å3, P21/n (No. 14), Z = 2; [(R)-C5H14N2][Zn(H2O)6](SO4)2 (2), a = 10.8665(2) Å, b = 7.8600(1) Å, c = 11.7029(2) Å, β = 116.283(1)°, V = 896.22(3) Å3, P21 (No. 4), Z = 2; [(S)-C5H14N2][Zn(H2O)6](SO4)2 (3), a = 6.5819(2) Å, b = 11.0014(2) Å, c = 12.5229(3) Å, β = 101.489(1)°, V = 888.62(4) Å3, P21 (No. 14), Z = 2.

PIPERAZINE; ORGANOZINC compounds; EVAPORATION (Chemistry); ENANTIOMERS; ZINC sulfate; AMINES; CRYSTAL structure; HYDROGEN bonding

Journal of Coordination Chemistry, 2012, Vol 65, Issue 7, p1178

0095-8972

Academic Journal

10.1080/00958972.2012.669476