Gold(I)-catalyzed oxidative rearrangements.

Intermediates possessing carbenoid character have recently been postulated in a number of gold-catalyzed rearrangements.1 In accord with this proposal, cyclopropane adducts are formed from the intermolecular reaction of the proposed gold(I)-carbenoid intermediates with olefins.2 To further examine the nature of these intermediates, we sought to explore their reactivity with reagents previously described as reactive toward metal carbenes. In this context, we were intrigued by the possibility that the electrophilic gold(I)-carbenoid intermediate might undergo oxygen atom transfer from a nucleophilic oxidant. While catalytic reactions involving oxygen atom transfer to metal carbenoids are rare,3 reports of oxygen atom transfer from sulfoxides to carbenes4 and metal carbenoids5 led us to investigate the reactivity of proposed gold(I)-carbenoid intermediates with these reagents. Herein we report the integration of these studies into the development of a series of gold(I)-catalyzed oxidative transformations.