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Dimerization reactions of aryl selenophen-2-yl-substituted thiocarbonyl S-methanides as diradical processes: a computational study.

ABSTRACT: An intriguing stepwise diradical mechanism of the dimerization of the reactive intermediate (thiocarbonyl S-methanide) appearing in the reaction of phenyl selenophen-2-yl thioketone with diazomethane was studied by means of computational methods. The preferred formation of the unusual macroheterocycle, competitive with the 1,3-ring closure leading to a thiirane and the head-to-head dimerization yielding a 1,4-dithiane derivative, respectively, was explained based on the analysis of the structure of the favored conformer of the intermediate, delocalized diradical species. The influence of selenium as a 'heavy atom' for stabilization of this intermediate has been emphasized.

SUBMITTER: McKee ML

PROVIDER: S-EPMC5355913 | biostudies-literature |

REPOSITORIES: biostudies-literature

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