Spectroscopic, Structural and Theoretical Studies on Matrix Photochemistry at Low Temperatures and Spectroscopic Properties of ã-Butyrothiolactone

NAHIR DUGARTE; MAURICIO F. ERBEN; ROSANA M. ROMANO; MAOFA GE; LI YAO; CARLOS O. DELLA VéDOVA

JOURNAL OF PHYSICAL CHEMISTRY A

AMER CHEMICAL SOC

Año: 2010 vol. 114 p. 9462 - 9470

1089-5639

The five-membered heterocyclic ã-butyrothiolactone was isolated in a low-temperature, inert Ar matrix, and the UV-visible (200 e ë e 800 nm)-induced photochemistry was studied. On the basis of the IR spectra, the formation of ethylketene (CH3CH2CHdCdO) was identified as the main channel of photodecomposition. The valence electronic structure was investigated by He(I) photoelectron spectroscopy assisted by quantum chemical calculations at the outer valence Green’s function/6-311++G(d,p) level of theory. The first three bands at 9.54, 9.69, and 11.89 eV are assigned to the nS, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.ã-butyrothiolactone was isolated in a low-temperature, inert Ar matrix, and the UV-visible (200 e ë e 800 nm)-induced photochemistry was studied. On the basis of the IR spectra, the formation of ethylketene (CH3CH2CHdCdO) was identified as the main channel of photodecomposition. The valence electronic structure was investigated by He(I) photoelectron spectroscopy assisted by quantum chemical calculations at the outer valence Green’s function/6-311++G(d,p) level of theory. The first three bands at 9.54, 9.69, and 11.89 eV are assigned to the nS, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.-visible (200 e ë e 800 nm)-induced photochemistry was studied. On the basis of the IR spectra, the formation of ethylketene (CH3CH2CHdCdO) was identified as the main channel of photodecomposition. The valence electronic structure was investigated by He(I) photoelectron spectroscopy assisted by quantum chemical calculations at the outer valence Green’s function/6-311++G(d,p) level of theory. The first three bands at 9.54, 9.69, and 11.89 eV are assigned to the nS, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.3CH2CHdCdO) was identified as the main channel of photodecomposition. The valence electronic structure was investigated by He(I) photoelectron spectroscopy assisted by quantum chemical calculations at the outer valence Green’s function/6-311++G(d,p) level of theory. The first three bands at 9.54, 9.69, and 11.89 eV are assigned to the nS, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.++G(d,p) level of theory. The first three bands at 9.54, 9.69, and 11.89 eV are assigned to the nS, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.S, nO, and ðCdO orbitals, respectively, denoting the importance of the -SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.-SC(O)- group in the outermost electronic properties. The conventional ring strain energy was determined to be 3.8 kcal mol-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.-1 at the G2MP2 level of calculation within the hyperhomodesmotic model.