AI Article Synopsis
- A chromium-catalyzed process was developed to create bromocyclopropanes from alkenes using bromoform as the reactant.
- An organosilicon compound was crucial for reducing chromium and producing a reactive bromomethylidene-chromium(iii) species necessary for the reaction.
- This cyclopropanation method effectively worked with different types of alkenes, including allyl ethers, allyl esters, and both terminal and cyclic alkenes.
Article Abstract
Chromium-catalyzed cyclopropanation of alkenes with bromoform was achieved to produce the corresponding bromocyclopropanes. In this catalytic cyclopropanation, an organosilicon reductant, 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-dihydropyrazine (), was indispensable for reducing CrCl(thf) to CrCl(thf), as well as for generation of (bromomethylidene)chromium(iii) species from (dibromomethyl)chromium(iii) species. The (bromomethylidene)chromium(iii) species are proposed to react spontaneously with alkenes to give the corresponding bromocyclopropanes. This catalytic cyclopropanation was applied to various olefinic substrates, such as allyl ethers, allyl esters, terminal alkenes, and cyclic alkenes.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8152687 | PMC |
| http://dx.doi.org/10.1039/d0sc00964d | DOI Listing |
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