Mass spectrometric study of tricarbonyl (eta(6)-phenyl methanols) of chromium(0)

Electronic substituent effects in the electron impact mass spectrometry of 2-(arylazo)-4-phenylphenols

A mass spectrometric study of a set of six novel 2-(arylazo)-4-phenylphenols 1-6 was performed. The electron impact spectra were acquired and analyzed for five of the compounds in order to establish a fragmentation pattern. The suggested pathways were investigated and confirmed by means of tandem mass spectrometry (MS/MS) experiments together with high-resolution accurate mass data. However, the sixth molecule, a sodium sulfonate salt, was studied using fast atom bombardment (FAB) ionization in positive and negative modes. In addition, some electronic substituent effects were investigated by analyzing Hammett-McLafferty linear free energy correlations for some peaks derived from the corresponding molecular ions. Also, the role of the O-H...N hydrogen bond present in the target compounds was analyzed. The roles of these H-bonds were consistent with the corresponding acidity constant values obtained experimentally as well as by theoretical quantum chemistry calculations using HF/6-31 + G(d,p) and B3LYP/6-31G(d,p). Some spectrometric data were correlated with topological properties derived from the atoms-in-molecules (AIM) theory.

Mass spectrometric studies of cyclopentanol derivatives in the reductive coupling of alpha,beta-unsaturated ketones assisted by samarium diiodide

The mass spectrometric fragmentations of a series of cyclopentanol derivatives in positive fast-atom bombardment (FAB(+)) mode were investigated. The corresponding pathways proposed were confirmed by MS/MS data obtained using linked scans at constant B/E, high-resolution accurate mass data, and comparisons with corresponding information for a specifically deuterated molecule.