Abstract
The mechanism associated with the base-promoted conversion of alkoxy-substituted and ring-fused gem-dihalocyclopropanes such as 40 into annulated furans has been explored. Treatment of compound 40 with potassium tert-butoxide affords a mixture of furans 23/27 and 41, an outcome that suggests the intermediacy of the slowly interconverting carbonyl ylides 42 and 43 that undergo rapid [1,5]-electrocyclizations and subsequent dehydrohalogenation to afford the observed products. This proposal is supported by ab initio MO and DFT calculations that also suggest a vinylcarbene insertion pathway is less likely to be operative.
Original language | English |
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Pages (from-to) | 13678-13690 |
Number of pages | 13 |
Journal | Journal of Organic Chemistry |
Volume | 83 |
Issue number | 22 |
DOIs | |
Publication status | Published - 16 Nov 2018 |