Synthetic Experiments in the Chrysene Series

Abstract

Vol. 01 anhydride dissolved in 200 cc. of neutral alcohol and titrated with 0.1 JV sodium hydroxide solution. To test the purity of the acid it was recovered and converted into phthalic anhydride. The quantitative isolation of the anhydride in this way was tested with a weighed sample which was converted into the salt, liberated and sublimed, and titrated. The recovery was 95.7%. In a second test a mixture of 1 g. each of the three phthalic acids gave a recovery of o-phthalic acid of 97%.We were unable to find a quantitative method for the separation of isophthalic and terephthalic acids. As a consequent*, the percentage of m-xylenes in the mixtures analyzed was considered to be the difference between the weights of the mixed xylenes and the sum of the ortho and para isomers. In several experiments the weight of wj-xylene was calculated from the weights of the pxylene and of the isophthalic and terephthalic acids obtained. The result checked within less than 1% the value obtained.

STUDIES ON LACTONES RELATED TO THE CARDIAC AGLYCONES. I. SYNTHESIS OF β-SUBSTITUTED Δα,β-BUTENOLIDES FROM ι-METHOXYMETHYL KETONES

“…Great difficulty was experienced in eliminating the hydroxyl group from this substance, and the synthesis has been abandoned in view of the relatively easy accessibility of the desired /3-formyl acid as described below. The observation of Stoermer ( 14) that half-ethers of primary-tertiary glycols are converted smoothly and in good yield to aldehydes when heated with acids or when fused with potassium acid sulfate (15) appeared to offer a more promising approach to the synthesis of the desired lactones.…”

“…Two products were isolated from the reaction-mixture: the above "^-saturated lactone (XII), and an aldehyde which has been identified as homotropic aldehyde (XIV). Inasmuch as the first step in the conversion of the half-ether of such a glycol to an aldehyde is apparently the formation of an enol-ether (XIII) (15), the formation of homotropic aldehyde can be readily explained by a decarboxylation of the enol ether ester (or acid) in a manner analogous to the very easy formation of 1,1,2-trimethyl-2-phenylethylene by distillation of ethyl a, a-dimethyl-/3-phenylvinylacetate (18). When IX was heated with potassium acid sulfate (15) the " ^-unsaturated lactone (XII) was formed exclusively.…”

Correlated Rotations and Unusual Fluorescence Properties ofperi-Substituted, Axially Chiral Naphthyl Ketones

“…1-Cyano-8-(dimethylamino)naphthalene (8) was synthesized from 8-amino-1-bromonaphthalene (11). [18,30] Firstly, 8-amino-1-bromonaphthalene was methylated with dimethyl sulfate by a standard method; [31] then the cyano compound 8 was obtained using CuCN in a Rosenmund-von-Braun reaction.…”

“…8-Amino-1-bromonaphthalene (10) [30] (1.9 g, 8.55 mmol) was treated with dimethyl sulfate (2.7 mL, 28.3 mmol). Purification by column chromatography (n-hexane/diethyl ether, 5:1) resulted in a colorless (slightly yellow) liquid.…”

The Synthesis of 1',9-Dimethyl-1,2-Benzanthracene

“…3) was very similar to that of 9-methyl-1,2-benzanthracene (IX) and all of the characteristic maxima, A-K, of the 1,2-benzanthracene system were clearly visible (9). In order to verify the fact that the l'-methyl group had not migrated during the dehydrogenation (10,11), hydrocarbon X was oxidized to a quinone (m.p. 188.0-189.6°) which failed to depress the melting point (189.6-190.6°) of an authentic sample of 1'-methyl-1,2-benzanthraquinone2 (1), and depressed the 1 It is of interest that the melting point of this picrate (123.2-124.4°) falls below that of the hydrocarbon (131.5-132.0°).…”