1. , Protective Groups in Organic Synthesis, 3rd ed., Wiley, New York, 1999, p. 150.
2. TsOH: A. C. Cope, E. C. Herrick, Org. Synth. Coll. Vol. 4, 1963, p. 304;
3. ZnCl2: R. H. Baker, F. G. Bordwell, Org. Synth. Coll. Vol. 3, 1955, p. 141;
4. A new acylation catalyst
5. NaOAc: The Miner Laboratories, Org. Synth. Coll. Vol. 1, 1941, p. 285;