... (5) For a review see: (a) Pearson, R. G. Hard and Soft Acids and Bases; Dowden, Hutchinson, & Ross Inc.: Stroudsberg, 1973. (b) Ho, TL Hard and Soft Acids and Bases Principle in Organic Chemistry; Academic Press: New York, 1977. ... Page 2. 7260 J. Org. Chem., Vol. 59, No. ...