Structure of O-alkyl-N-ethoxycarbonyl-Thiocarbamate and Imidothiocarbonate Derivatives

V. M. CAYÓN; S. E. TORRICO VALLEJOS; C. O. DELLA VÉDOVA; O. E. PIRO; G. A. ETCHEVERRÍA ; M. F. ERBEN

Research Trends in Organic Chemistry

Research Trends

Lugar: Nueva Delhi; Año: 2018 vol. 19 p. 43 - 73

0972-4362

O-methylN-ethoxycarbonylthiocarbamate, CH3CH2OC(O)N(H)C(S)OCH3 (I) (LST4), and O-ethyl N-ethoxycarbonylthiocarbamate, CH3CH2OC(O)N(H)C(S)OCH2CH3(II) (LST2), were prepared by the addition reaction between the CH3CH2OC(O)NCS and thecorresponding alcohols. The structural and conformational properties were studied using low-temperature single crystal X-ray diffraction and vibrational spectroscopy assisted by quantum chemical calculations. Compound I crystallizes in the monoclinic space group P21/n with a = 4.2450(1), b = 18.4992(5), c = 9.8759(3) Å, β = 95.887(3)°. and Z = 4 molecules per unit cell, and II in the triclinic space group with a = 4.1771(8), b = 9.235(2), c = 11.804(2) Å, α = 98.17(1), β = 98.62(1), γ = 102.29(2)°, and Z = 2. In the crystal, the conformation around the thiocarbamate group ?OC(S)N(H)? is characterized by a synperiplanar orientation of the C=S double with respect to the N?H single bond, while the methoxycarbonyl C=O double bond is in antiperiplanar orientation with respect to the N?H bond. Both species form dimers linked by NH...S=Chydrogen bond,theNH...S=C distance being 3.352(2) Å in compound I. Furthermore, ethoxycarbonylimidothiocarbonate especies were obtained by the addition of methyl and butyl groups to the C=S double bond of I and II. Thus, species with formula CH3CH2OC(O)N=C(SCH3)OCH3 (III), CH3CH2OC(O)N=C(SCH3)OCH2CH3 (IV), as well as the novel compounds CH3CH2OC(O)N=C(SC4H9)OCH3(V) and CH3CH2OC(O)N=C(SC4H9)OCH2CH3 (VI), were also prepared and fully characterized by spectroscopic methods.