Rhodium(III)-Catalyzed Synthesis of N-(2-Acetoxyalkyl)isoquinolones from Oxazolines and Alkynes through C-N Bond Formation and Ring-Opening

An atom-economic approach for the synthesis of N-(2-acetoxyalkyl)isoquinolones from oxazolines and alkynes through rhodium(III)-catalyzed auto-tandem reactions involving C-H bond functionalization/C-N bond formation/ring opening/nucleophilic substitution is described. This protocol features high regioselectivity, tolerance of various functional groups, and retention of absolute configuration of chirality. Exploration of the reaction mechanism reveals that Cu(OAc)(2) not only acts as the oxidant, but also provides acetate to promote the reaction in this process.