Crystal structure and spectroscopic properties of N- methoxycarbonylsulfenyl-substituted ureas, CH3OC(O)SN(H)C(O)NRR´ [R = H, R´ = C(CH3)3 and R = R´ = CH2CH3]

S. TORRICO-VALLEJOS; M. F. ERBEN; S. GÓMEZ RUIZ; E. HEY-HAWKINS; G. A. ECHEVERRÍA; O. E. PIRO ; C. O. DELLA VÉDOVA

JOURNAL OF MOLECULAR STRUCTURE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2013 vol. 1037 p. 116 - 121

0022-2860

Abstract. Structural and spectroscopic properties of N,N-diethyl- (I) and N-tert-butyl-N?-methoxycarbonylsulfenyl urea (II) are analyzed using a combined approach with data obtained from X-ray diffraction, vibrational spectra and quantum chemical calculations. The molecular structures of CH3OC(O)SN(H)C(O)N(CH2CH3)2 (I) and CH3OC(O)SN(H)C(O)N(H)C(CH3)3 (II), the later co-crystallized with ethyl acetate (II.½EtOAc), were determined by X-ray diffraction methods. Compound I crystallizes in the triclinic space group P-1 with a = 7.9471(4), b = 8.6672(4), c = 16.0447(8) Å, a = 80.335(4), b = 87.087(4), g = 75.271(4)º, and Z = 4 molecules per unit cell and II·0.5EtOAc in the orthorhombic space group Pnma with a = 9.365(5), b = 26.577(5), c = 10.287(5) Å, and Z = 8. The structures were solved from 3377 (I) and 1614 (II·0.5EtOAc) reflections with I>2s(I) and refined to R1 factors of 0.0410 (I) and 0.0441 (II·0.5EtOAc). In I, there are two independent but closely related molecules in the asymmetric unit whose conformations differ only in the orientation of the terminal N(CH2CH3)2 groups. Neighboring molecules in I exhibit N-H···O interaction giving rise to a polymeric chains. The conformation of the O-(C = O)-S-N-(C = O)-N skeleton of II is almost identical to the corresponding one of both molecules of I. Neighboring molecules in II are linked through bifurcated N-H···O···H-N interactions giving rise to a polymeric chain. The vibrational properties have been studied by FTIR and FT-Raman spectroscopy along with quantum chemical calculations at the B3LYP/6-311+G* level.