RESUMO

The reaction of p-fluoroaniline and SOCl2 rendered p-fluorosulfinylaniline in good yield. The obtained dark yellowish liquid compound was characterized by NMR, UV-visible, FT-IR and Raman spectroscopies. The observed features were consistent with the existence of only one conformer, belonging to the CS symmetry group. A tentative assignment of the vibrational modes was performed on the basis of experimental spectra and quantum chemical calculations at different levels of theory (B3LYP and MP2 with 6-31+G(d), 6-311+G(d) and 6-311+G(df) basis sets). The conformational and vibrational properties of p-fluorosulfinylaniline were in good agreement with experimental data reported for other substituted sulfinylanilines and p-halogenanilines.

Assuntos

Compostos de Anilina/química , Técnicas de Química Sintética , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Vibração

RESUMO

The electronic properties of fluorosulfonyl isocyanate, FSO2NCO, were investigated by means of photoelectron spectroscopy and synchrotron based techniques. The first ionization potential occurs at 12.3 eV and was attributed to the ejection of electrons formally located at the π NCO molecular orbital (MO), with a contribution from nonbonding orbitals at the oxygen atoms of the SO2 group. The proposed interpretation of the photoelectron spectrum is consistent with related molecules reported previously and also with the prediction of OVGF (outer valence green function) and P3 (partial third order) calculations. The energy of the inner- and core-shell electrons was determined using X-ray absorption, measuring the total ion yield spectra, and the resonances before each ionization threshold were interpreted in terms of transitions to vacant molecular orbitals. The ionic fragmentation mechanisms in the valence energy region were studied using time-of-flight mass spectrometry as a function of the energy of the incident radiation. At 13 eV the M(+) was the only ion detected in the photoion-photoelectron-coincidence spectrum, while the FSO2(+) fragment, formed through the breaking of the S-N single bond, appears as the most intense fragment for energies higher than 15 eV. The photoion-photoion-photoelectron-coincidence spectra, taken at the inner- and core-levels energy regions, revealed several different fragmentation pathways, being the most important ones secondary decay after deferred charge separation mechanisms leading to the formation of the O(+)/S(+) and C(+)/O(+) pairs.