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An improved one-pot synthesis of SMCC (IV), a valuable heterobifunctional linker in pharmaceutical chemistry, is described.

Aryl-substituted epoxides undergo smooth rearrangement in the presence of 0.01–0.1 mol% Bi(OTf) 3 · x H 2 O. The rearrangement is regioselective with aryl-substituted epoxides, and products arise from cleavage of the benzylic CO bond. The highly catalytic nature of this method coupled with the fact that the reagent is relatively non-toxic, easy to handle and inexpensive make it an attractive alternative to more corrosive and toxic Lewis acids, such as BF 3 ·Et 2 O, currently used to effect epoxide rearrangements.

Nitrogen heterocycles can be prepared by performing ring-expansion reactions of γ-silyloxy-γ-lactams, which are available by the annulation reactions of allylic silanes. Nucleophilic substitution of the annulation products and subsequent translactamization of nitrogen-tethered γ-lactams provide six-, seven-, and eight-membered ring lactams. An enantiomerically enriched δ-lactam formed from this method was elaborated to form the hydroxypiperidine core structure of the pseudodistomin alkaloids.