A new thermal isomerization of polyynes is described. Benzyne intermediates substituted by a C(RR′)OR′′ substituent adjacent to one of the benzyne sp-hybridized carbons give rise to products in which the OR′ moiety has migrated to the proximal benzyne carbon. This process likely proceeds via sequential formation of multiple reactive intermediates: an initial thermally generated benzyne, a strained benzoxetenonium ion, and an o-quinone methide. As some examples demonstrate, the overall transformation can be quite efficient. The mechanism of this novel reaction is further supported by experiments and DFT calculations.
Bibliographical noteFunding Information:
This work was supported by the Institute of General Medical Sciences of the U.S. Department of Health and Human Services (R35 GM127097) and the National Science Foundation (CHE-1665389). Most of the NMR data were obtained with an instrument acquired through the NIH Shared Instrumentation Grant program (S10OD011952).
PubMed: MeSH publication types
- Journal Article
- Research Support, N.I.H., Extramural
- Research Support, U.S. Gov't, Non-P.H.S.