Symmetrically Substituted Thiourea Derivatives

Unsymmetrically Substituted Thioureas. 1,1-Dimethyl-3-o-tolylthiourea and 1,1-Diethyl-3-o-tolylthiourea

“…The details are: N1...S i 3.423 (3) A and NlmH1...S i 140 (3) ° for DMTTU; N1...S ii 3.363 (2),~, and NI~H1...S ii 147(2) ° for DETTU [symmetry codes: (i) -x, y l 3 2, 2 z; (ii) -x, y + ½, 3_ z]. The N~H...S angles observed here are less than those observed in symmetrical thioureas (Ramnathan et al, 1995).…”

“…The CI--~-S bond lengths observed in both structures are greater than the mean value (1.681/~) given by Allen et al (1987). The two Csp2mN distances, C1--N1 and ClaN2, show different magnitudes, whereas similar differences are not found in symmetrically substituted thiourea derivatives (Ramnathan et al, 1995).…”

“…The angles around atom C1 show appreciable differences compared to other unsymmetrical thioureas (Ranmathan & Sivakumar, unpublished results); the N1---C1--N2 angles [115.6(3) and 115.6(1) °, respectively] observed in these two structures are more acute than those observed in symmetrical thioureas (Ramnathan et al, 1995). The dihedral angles between the planes of the thiourea moiety and the tolyl ring are 121.4(1) (DMTTU)and 116.7(1) ° (DETTU).…”

1-Cyclohexyl-3-phenylthiourea

“…The two substituent groups (phenyl and cyclohexyl) are oriented in a cis-trans configuration with respect to the C=S bond. So far, the cis-cis configuration has been observed in both (II) and 1,3-diphenylthiourea (Ramnathan et al, 1995b). Contrary to our expectation that molecule (II), with the methyl group in an ortho position (C7), would prefer the cis-trans configuration and molecule (I) the cis-cis configuration, the results turn out be the other way around.…”

FT-IR, FT-Raman and ab-initio studies of 1,3-diphenyl thiourea

“…C4-N8=1.4122 Å, bond angles C11-N10-C9=129.7, N10-C9-N8=114.3, N10-C9-S23= 116.8, S23-C9-N8=128.8, C9-N8-C4=130.7, N8-C4-C5=124.7 º and the dihedral angles C11-N10-C9-S23=-173.4, C4-N8-C9-S23=-1.8, C4-N8-C9-N10=179.1º, which are in agreement with the corresponding values for the title compound. Ramnathan et al [40] reported C9-S23=1.7073, C4-N8=1.445, C11-N10=1.4375 Å, C9-N8-C4=127.8 º, C9-N10-C11=125.5 º, N8-C9-N10=117.3º, N8-C9-S23= 120.4º, N10-C9-S23=122.2º, whereas the corresponding values in the present case are, 1.6636, 1.4188, 1.4188 Å, 128.6, 128.6, 110.1, 124.9, and 124.9 º.…”