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SummaryArylnaphthyl ketones condense with diethyl succinate yielding the stereoisomeric half-esters 2a-2d which were subjected to a series of reactions leading to 1-phenylphenanthrene and 1,l'-binaphthyl derivatives. (E)-3-Ethoxycarbonyl-4-(4-methoxynaphth-l-yl)-4-arylbut-3-enoic acids (2b-d) were converted finally into the corresponding naphtho [ 1,2-c]fluorenones (9). The structure of the products was established by IR. and UV. spectroscopy. The effect of substituents on the relative proportions of (E)-and (Z)-half-esters 2 was determined by chromatography and UV. spectroscopy. Awad et al.[ 13 claimed that the condensation of 1-benzoylnaphthalene (1 a) with diethyl succinate in the presence of potassium t-bitoxide in t-butyl alcohol produced ( E ) half-ester 2a as the sole product. This result was attributed either to steric or/and polar factors. We have now found that the (Z)-2a isomer is also produced.In order to study the r6le of the above mentioned factors in determining the ratio of the isomeric half-esters produced in this Stobbe condensation, aryl naphthyl ketones containing substituents of different polar nature either in the naphthyl or in both the naphthyl and the phenyl groups, 1 -benzoyl-4-methoxynaphthalene (1 b), l-(p-methoxybenzoyl)-4-methoxynaphthalene (1 c) and 1-@-chlorobenzoy1)-4-methoxynaphthalene (Id), besides 1-benzoylnaphthalene (1 ai) were condensed with diethyl succinate.The new ketones l c and I d were prepared by Friedel-Crajts condensation of p-methoxybenzoyl and p-chlorobenzoyl chloride with 1 -methoxynaphthalene [2].I -Benzoylnaphthalene (1 a) and diethyl succinate. After condensation of 1-benzoylnaphthalene (1 a) with diethyl succinate [ 11, the crude half-ester mixture 2a (53%) was directly cyclized with sodium acetate in acetic anhydride. After crystallization the neutral product gave 1-acetoxy-3-ethoxycarbonyl-4-phenylphenanthrene (3a) (84%). Chromatography of the residue gave 4-acetoxy-2-ethoxycarbonyl-1,l'-binaphthyl (4a) (13%). The same relative amounts of 3a and 4a were estimated by the application of Dewar & Urch spectrophotometric method [3].

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