Synthesis, XRD and Mechanistic Studies of α-Aryl-β,β-ditosyloxy Ketones: An Oxidative 1,2-Aryl Migration in α,β-Unsaturated Diaryl Ketones Under Metal Free Conditions

The given study investigates and validates [hydroxy (tosyloxy)iodo]benzene (HTIB) mediated oxidative 1,2-aryl C-C migration in variegated alpha,beta-unsaturated diaryl ketones. This oxidative-skeletal rearrangement ultimately outgrowth to alpha-aryl-beta,beta-ditosylm ketones in presence of CH2Cl2. The structure of products has been very well established using various spectral techniques H-1 & C-13-NMR, IR and single crystal XRD. The generality of fascinating 1,2-aryl C-C migration was thoroughly investigated and verified by electronic (EDG/EWG) and steric factors on different derivatives of alpha,beta-unsaturated diaryl ketones. Mechanism of 1,2-aryl C-C migration has also been supported by computational studies using B3LYP-D3 level of theory. Aesthetically this novel and unique three carbon component would expose a direct and conceptually robust strategy to access regioselective synthesis of 4,5-diaryl isoxazoles, 4,5-diaryl pyrazoles and 1,4,5-triaryl pyrazoles and also efficient access to desoxybenzoin and other important beta,beta-difunctionalized chemical entities.