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

SONIA TORRICO-VALLEJOS; MAURICIO F. ERBEN; SANTIAGO GÓMEZ RUIZ; EVAMARIE HEY-HAWKINS; GUSTAVO A. ECHEVERRÍA; OSCAR E. PIRO; CARLOS O. DELLA VÉDOVA

JOURNAL OF MOLECULAR STRUCTURE THEOCHEM

ELSEVIER SCIENCE BV

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

0166-1280

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 (EtAc) solvent molecule to give the adduct  II.½EtAc, were determined by X-ray diffraction methods. were determined by X-ray diffraction methods. Compound I crystallizes in the triclinic P-1 space group 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.½EtAc in the orthorhombic Pnma with 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.½EtAc) reflections with I>2s(I) and refined to agreement R1-factors of 0.0410 (I) and 0.0441 (II.½EtAc). In the I solid there are two independent but closely related molecules in the crystal asymmetric unit whose conformations differ only in the chirality of the terminal -N(CH2-CH3)2 groups. Neighboring I molecules are N-H…O bonded to each other giving rise to a polymeric arrangement. The conformation of the O-(C=O)-S-N-(C=O)-N skeleton of II in the II.½EtAc solid is nearly the same as the corresponding one of both 1 molecules. Neighboring II molecules in the lattice are linked through a bifurcated N-H…O…H-N bonds 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.