CRYSTAL AND MOLECULAR-STRUCTURES OF P,P-DICYCLOHEXYL-N-METHYL-PHOSPHINYLTHIOFORMAMIDE, P,P-DICYCLOHEXYL-N-PHENYL-PHOSPHINYLTHIOFORMAMIDE, DICYCLOHEXYL-N-METHYL-THIOPHOSPHINYLTHIOFORMAMIDE, AND -DICYCLOHEXYL-N-PHENYL-THIOPHOSPHINYLTHIOFORMAMIDE

The crystal structures of the title compounds P,P-dicyclohexyl-N-methy l-phosphinylthioformamide, [(c)Hex2P(O)C(S)N(H)Me], C14H26ONPS, P,P-di cyclohexyl-N-phenylphosphinylthioformamide, [(c)Hex2P(O)C(S)N(H)Ph], C 19H28ONPS, -dicyclohexyl-N-methylthiophosphinylthioformamide, [(c)Hex2 P(S)C(S)N(H)Me], C14H26NPS2, and dicyclohexyl-N-phenyl-thiophosphinylt hioformamide, [(c)Hex2P(S)C(S)N(H)Ph], C19H28NPS2, have been determine d at room temperature. The green crystals of [(c)Hex2P(O)C(S)N(H)Me] a re monoclinic, space group C2/c, with unit cell dimensions a = 10.247( 2) angstrom, b = 16.025(4) angstrom, c = 19.358(4) angstrom, beta = 97 .75(2)-degrees, Z = 8 and D(x) = 1.212 Mg m-3. Crystals of [(c)Hex2P(O )C(S)N(H)Ph] are also monoclinic, space group C2/c, with unit cell dim ensions a = 14.856(4) angstrom, b = 11.666(4) angstrom, c = 22.039(3) angstrom, beta = 95.59(1)-degrees, Z = 8 and D(x) = 1.221 Mg m-3. The colorless crystals of [(c)Hex2P(S)C(S)N(H)Me] are orthorhombic, crysta llizing in the Pnma space group with dimensions a = 10.2600(9) angstro m, b = 15.447(2) angstrom, c = 10.141(3) angstrom, Z = 4 and D(x) = 1. 254 Mg m-3. Yellow crystals of [(c)Hex2P(S)C(S)N(H)Ph] are triclinic, space group P1BAR, with dimensions a = 9.766(2) angstrom, b = 11.111(2 ) angstrom, c = 9.388(2) angstrom alpha = 100.54(2)-degrees, beta = 10 4.66(1)-degrees and gamma = 83.86(1)-degrees, Z = 2 and D(x) = 1.249 M gm-3. The structures were solved by direct-methods and each refined by a full-matrix least-squares procedure to final R = 0.036 (0.046; 0.04 0; and 0.038) using 1383 (1257; 1362; and 2758) reflections for each o f the above [(c)Hex2P(Y)C(S)N(H)R] (where Y = O or S and R = Me or Ph) compounds, respectively. The conformation about the C-N bond in each of [(c)Hex2P(Y)C(S)N(H)R] is Z. Important parameters for Y = O, R = Me : P = O 1.480(2), P - C 1.814(4), C = S 1.630(3) and C - N 1.306(4) an gstrom; Y = O, R = Ph: P = O 1.479(4), P - C 1.817(5), C = S 1.618(5) and C - N 1.327(6) angstrom; Y = S, R = Me : P = S 1.942(1), P - C 1.8 23(4), C = S 1.644(4) and C - N 1.290(5) angstrom; and Y = S, R = Ph: P = S 1.9495(9), P - C 1.846(3), C = S 1.624(2) and C - N 1.317(3) ang strom. Symmetry related molecules of [(c)Hex2P(O)C(S)N(H)R] associate in the lattice via hydrogen bonding contacts. The P - C(1) bond distan ces in the [(c)Hex2P(Y)C(S)N(H)R] compounds are shown to be significan tly shorter than those found in the related [Ph2P(Y)C(S)N(H)R] compoun ds.