O. A. Solov'ev

Mass spectrometric study of linear and angular pyrrolodibenzofurans, pyrrolodibenzothiophenes, and pyrrolocarbazoles

The analysis of the mass spectra of unsubstituted pyrrolodibenzofurans and α-carboxy- and α-carbethoxypyrrolodibenzofurans, α-carboxy- and α-carbethoxy-pyrrolodibenzothiophenes, and α-carbethoxypyrrolocarbazoles, in which the pyrrole ring is fused to faces a, b, or c, permits finding the differences in the relative intensities of the peaks of their fragmentary ions due to the presence of additional free reactions in these structures or different internal stabilization of the fragmentary ions. The mass spectral characteristics which make it possible to identify the type of fusion of the pyrrole ring by comparison of the mass spectra of pairs of isomers are reported.

Synthesis and reactions of benzoformylindoles

A method was developed for the synthesis of 5- or 6-formylindoles by reaction of 5- or 6-aminomethylindoles with hexamethylenetetramine in acidic media. 1-Methyl-7-formylindole was obtained by recyclization of nicotyrine methiodide under the influence of alkaline agents. The corresponding vinylindoles were obtained by condensation of formylindoles with nitromethane, nitroethane, and malonic acid. The structures of the products were proved by alternative synthesis, the results of elementary analysis, and the UV, IR, PMR, and mass spectra.

MASS-SPECTRAL BEHAVIOR OF NITROHYDROXY- AND NITROMETHOXYMETHYLINDOLES

The principal pathways in the fragmentation of isomeric nitrohydroxy- and nitromethoxymethylindoles containing functional groups in the benzene ring were established by means of high-resolution mass spectrometry and deuterium labeling. The fragmentation of these compounds proceeds via different pathways as a function of the orientation of the functional substituants and the pyrrole nitrogen atom and differs from the fragmentation of other nitroarenes. The data obtained make it possible to reliably identify isomeric substances.