SEARCH

SEARCH BY CITATION

Keywords:

  • cyclobutenones;
  • density functional calculations;
  • photochemistry;
  • rearrangements;
  • small ring systems
Thumbnail image of graphical abstract

Go with the flow: 4-Hydroxycyclobutenones were efficiently transformed into 5H-furanones using an inexpensive flow-photochemical setup. The results challenge the notion that this and the related thermochemical rearrangement display torquoselectivity in their electrocyclic opening to a vinylketene intermediate. Selectivity in the photochemical rearrangement is due a dichotomous reactivity of the (E)- and (Z)-vinylketene intermediates (see scheme).