American Chemical Society Acta Medica Okayama 15237060 21 8 2019 Chromium-Mediated Stannylcyclopropanation of Alkenes with (Diiodomethyl)stannanes 2668 2672 EN Masahito Murai Graduate School of Natural Science and Technology, Okayama University Ryuji Taniguchi Graduate School of Natural Science and Technology, Okayama University Chisato Mizuta Graduate School of Natural Science and Technology, Okayama University Kazuhiko Takai Graduate School of Natural Science and Technology, Okayama University A stannyl-group-substituted gem-dichromiomethane species, generated in situ from CrCl2, TMEDA, and tributyl(diiodomethyl)stannane, worked as an efficient stannylcarbene equivalent to promote cyclopropanation of alkenes. The reaction provided synthetically useful stannylcyclopropanes directly from commercially available unactivated alkenes without using potentially flammable alkylzinc and diazo compounds. Structural characterization of stannyl- and germyl-group-substituted gem-dichromiomethane complexes and the effect of group 14 elements containing substituents for cyclopropanation are also described. No potential conflict of interest relevant to this article was reported.