A new reaction of diazomethane with norbornyl α-diketones in MeOH as solvent leading regioselectively to ketals is described. The mechanistic details of this intriguing reaction were investigated employing d4-MeOH, EtOH and d6-EtOH. The surprising observation of complete deuterium incorporation in the diazomethane-derived methoxy group was accounted for by sequential deuterium exchange between the initially formed hemiketal d 4-18 and diazomethane in the presence of d4-MeOH as solvent.
Bibliographical noteFunding Information:
This work was supported by the Department of Science and Technology (DST), New Delhi. F.A.K. acknowledges the DST for a Swarnajayanti Fellowship. R.S., C.S. and C.N.R. thank CSIR/UGC for fellowships.
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