Photodecarboxylative C–H Alkylation of Azauracils with <i>N</i>-(Acyloxy)phthalimides
Satya Prakash Panda, Sudhir Kumar Hota, Rupashri Dash, Lisa Roy, Sandip Murarka
Abstract
We disclose a transition-metal-free NaI/PPh 3 -mediated direct C–H alkylation of azauracils using N -(acyloxy)pthalimides (NHPIs) as readily available alkyl surrogates under visible light irradiation. Detailed mechanistic studies reveal formation of a photoactivated electron donor–acceptor (EDA) complex between NaI/PPh 3, TMEDA, and alkyl NHPI ester and establish the crucial role of TMEDA in increasing the activity of the photoredox system. The reaction demonstrates a broad scope, scalability, and appreciable functional group tolerance. A variety of azauracils are shown to undergo alkylation by primary, secondary, and tertiary NHPI esters under mild conditions, furnishing the desired products in good to excellent yields.