Phosphorylation reagent. Prepn: G. Jacobsen, Ber. 8, 1519 (1875); R. Anschütz, W. O Emery, Ann. 253, 105 (1889). Activation of carboxyl groups: H.-J. Liu, S. I. Sabesan, Can. J. Chem. 58, 2645 (1980); for lactam synthesis: J. M. Aizpurua et al., Tetrahedron Lett. 25, 3905 (1984); L. Banfi, G. Guanti, ibid. 43, 7427 (2002). Oxidative rearrangements: H.-J. Liu, J. M. Nyangulu, ibid. 30, 5097 (1989); J. P. Jeyadevan et al., J. Med. Chem. 47, 1290 (2004). Brief review: A. K. Adak, Synlett 2004, 1651-1652.