THE PHENANTHRENE NUCLEUS 129 for acids containing substituents both on the side chain M-66-56 and in the nucleus. 67 In one instance the isolation of a small but significant amount of the isomeric 3,4-benzphenanthrene derivative arising from 3,4-cyclization was reported. 66 Although cyclization of 7-2-phenan-thrylbutyric acids generally seems to favor the formation of the chrysene structure, in the unsubstituted acid the ring may be induced to close either into the 3- or 1-position, 43 depending upon the experimental method used for cyclization (see p. 176). From this observation^ it appears that no valid generalization can be made regarding the propor-tion of isomers formed in any ring closure which ^has the inherent tend-ency to take place in two directions. A number of the following cycliza-tions fall into this category. The cyclization of /3-phenanthrylpropionic acids proceeded in two directions a when the acid side chain is located at the 1- or 9-position, giving mixtures of ketones LXV and LXVT from the 1- and LXXIV and
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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.