126 THE FORMATION OF CYCLIC KETONES from acylation at the adjacent 2-position of the nucleus. The alternative direction of cyclization is into the peri position, involving the formation of a seven-membered ring. The inherent resistance to this reaction may be overcome, in part, by the presence of activating groups appropriately situated (see p. 175, formulas XCIII through XCV). The peri ring closure is generally predominant, however, with /3-1-naphthylpropionic acids. 86-36> "• 38> 39 The course of the reaction is probably decided by the preference of six- over five-membered ring formation, although doubtless the activities of the 8- and the 2-positions are not identical. In at least one instance 37 some of the five-membered ring product of 1,2-cyclization was formed. 4,5-Benzhydrindone-l (LXIII) was isolated in 6% yield from the cyclization of /3-1-naphthylpropionic acid (LXI) in addition to an 81% yield of 7-perinaphthanone (LXII).0
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This note was uploaded on 11/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.