The first pi complex of copper(I) sulfate: Synthesis and crystal structureof [Cu(CH2=CH-CH2-NH3)(SO4)]

The crystals of [Cu(CH2=CH-CH2-NH3) (SO4)] were obtained by an ac electroch emical synthesis from N,N'-diallylguanidinium sulfate (which undergoes hydr olysis) and an ethanol solution of Cu(NO3)(2) . 3H(2)O. The title compound was structurally characterized with the use of a twin crystal (a DARCh diff ractometer, MoKalpha radiation, space group P2(1)/n, a = 13.288(4) Angstrom , b = 4.976(3) Angstrom, c = 9.932(2) Angstrom, gamma= 97.47(4)degrees, V= 651.1(5)Angstrom(3); Z = 4, R = 0.037 from 761 reflections with F greater t han or equal to 2 sigma F). The copper(I) atom has a trigonal-pyramidal env ironment made by three oxygen atoms from different sulfate groups and the C =C bond in the equatorial plane. The coordinated C=C bond length is equal t o 1.38(1) Angstrom. The structure is built from chains arranged along the [ 010] axis, in which the SO42- anion coordinates with three metal atoms thro ugh two oxygen atoms. Effective charges on atoms were calculated to elucida te the role of the N-H ... O hydrogen bonds in the sulfate anions functioni ng as acidoligands.