U. Niedballa, H. Vorbrüggen, Angew. Chem. Int. Ed. 9, 461 (1970).
The reaction of silylated heterocyclic bases with peracylated sugars in the presence of Lewis acids to yield natural β-nucleosides. If the sugar lacks a 2α-acyloxy substituent, an anomeric mixture forms:

Scope and limitations: H. Vorbrüggen et al., Ber. 114, 1234 (1981). Mechanistic study: H. Vorbrüggen, G. H"ofle, ibid. 1256. Synthetic applications: U. Niedballa, H. Vorbrüggen, J. Org. Chem. 39, 3654, 3660, 3664, 3668, 3672 (1974); R. O. Dempcy, E. B. Skibo, ibid. 56, 776 (1991); S. H. Kawai, G. Just, Nucleosides Nucleotides 10, 1485 (1991). Cf. Hilbert-Johnson Reaction.