Di Filippo M, Baumann M. Carbene-controlled regioselectivity in photochemical cascades.
Org Biomol Chem 2023;
21:2930-2934. [PMID:
36745509 DOI:
10.1039/d3ob00122a]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A highly regioselective route to complex carbocyclic scaffolds through a continuous photochemical process is reported. Crucially, we uncovered that ortho substitutents on the right-hand aryl ring are placed away from a transient carbene species which induces the exclusive regioselectivity observed. By varying the non-symmetrically substituted aryl moiety, we demonstrate how the product outcome favors cyclobutenes for electron-poor and neutral substituents and cycloheptatrienes for more electron-rich systems. Additionally, a photochemically induced rearrangement was uncovered for highly electron-rich substrates that ultimately generates complex hydroperoxides. Overall, this facile one-step process is fast and high yielding and demonstrates the power of photochemistry towards the exploration of new chemical space.
Collapse