X-ray structural investigations: I. Two alkaline earth metal complexes; II. Triphenylphosphine oxide silver (I) nitrate; III. Two molecular complexes of 18-crown-6; IV. 2-(4,5-benzo-1,3-dithiol-2-ylidene)-cyclohexanone; V. Bis-bicyclo-[3.3.1]-nona-9-ylidene

Abstract

Crystalline Bis(bipyridyl)Barium Thiocyanate is a complex containing an eight coordinate Barium. The barium atom is coordinated by two thiocyanate and four bipyridyl nitrogen atoms and two sulfur atoms from symmetry related thiocyanates. Neighboring barium ions are bridged by thiocyanate groups forming long chains through the crystal. The coordination polyhedron has square antiprismatic geometry. The cell parameters for the monoclinic crystal, in space group C2/c are a = 17.047(7) (ANGSTROM), b = 10.127(5) (ANGSTROM), c = 14.371(4) (ANGSTROM) and (beta) = 116.61(3) degrees. Bis(bipyridyl)Calcium Thiocyanate Monohydrate in crystalline form contains a seven coordinate Calcium. Coordination is by two thiocyanate and four bipyridyl nitrogen atoms and the oxygen atom of the water of hydration. The coordination polyhedron is a monocapped trigonal prism. The cell parameters for the monoclinic crystal in space group P21/c, are a = 16.33(1) (ANGSTROM), b = 9.851(3) (ANGSTROM), c = 14.802(7) (ANGSTROM) and (beta) = 97.91(5) degrees. Triphenylphosphine oxide Silver(I) Nitrate is a five coordinate complex in which Silver is coordinated by the oxygen atom of the phosphine oxide and by four oxygen atoms of two related nitrates. The donor atoms form a square pyramid around the silver atom. Neighboring silver atoms are bridged by one nitrate oxygen atom, forming long chains through the crystal. The cell parameters for the orthorhombic crystal in space group P(,212121) are a = 13.444(5) (ANGSTROM), b = 15.066 (3) (ANGSTROM) and c = 8.664(2) (ANGSTROM). In the two complexes of 18-Crown-6, the molecules are coupled by hydrogen bonding interactions and the rings have approximate D3d symmetry. The 2:1 complex of Formamide and 18-Crown-6 crystallizes in triclinic space group P(')1 with cell parameters a = 8.115(5) (ANGSTROM), b = 8.194(7) (ANGSTROM), c = 7.700(6) (ANGSTROM), (alpha) = 90.89(7) degrees, (beta) = 111.22(5) degrees and (gamma) = 98.34(6) degrees. The 1:1 diaquo complex of 4,4'-Dihydroxybiphenyl and 18-Crown-6 crystallizes in monoclinic space group P21/c with cell parameters a = 9.264(1) (ANGSTROM), b = 11.007(2) (ANGSTROM), c = 14.165(2) (ANGSTROM) and (beta) = 109.10(1) degrees. 2-(4,5-Benzo-1,3-dithiol-2-ylidene)-cyclohexanone crystallizes in monoclinic space group P21/c with cell parameters a = 6.459(1) (ANGSTROM), b = 14.262(3) (ANGSTROM), c = 13.514(4) (ANGSTROM) and (beta) = 112.16(2) degrees. Bis-bicyclo-{3.3.1}-nona-9-ylidene crystallizes in a monoclinic unit cell in two independent molecules. The two molecules are in the all chair conformation with transannular contacts of 1.99(3) and 1.81(8) (ANGSTROM). The monoclinic crystal, in space group C2/m has cell constants of a = 14.257(6) (ANGSTROM), b = 15.015(6) (ANGSTROM), c = 6.895(2) (ANGSTROM) and (beta) = 93.21(3) degrees.