Aspirin anion appears to exist only fleetingly, rearranging via acetyl transfer to the ortho carboxylate group, as indicated by IR, UV and NMR. The resulting mixed anhydride cyclises to the more stable bicyclic orthoacetate isomer, a process facilitated by time and increasing pH. Mechanistic possibilities are discussed to explain these intriguing observations.
Bibliographical noteFunding Information:
We thank University Grants Commission (New Delhi) for a D. S. Kothari postdoctoral fellowship to H.V.K. We also remain grateful to a referee for several constructive suggestions which led to a vastly improved manuscript.
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