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Amino acids containing cycloaliphatic groups have been neglected in the search for fiber-forming polymers although w-aminocarboxylic acids and their derivatives have received considerable attention. Two cycloaliphatic amino acids, p-and maminomethylcyclohexylcarboxylic acid, were prepared in our laboratory. The meta compound (I) has not previously been reported in the literature; the only preparation of the para compound (11) reported involved a chemical reduction of p-aminomethylbenzoic acid prepared from p-cyanobenzyl-ch1oride.l Our three-step synthesis is illustrated in H z N C H 2 V C O 2 H the accompanying scheme. The starting material may be m-or p-tolunitrile depending upon the amino acid desired.The p-cyanobenzoic acid prepared from p-tolunitrile by chromium trioxide oxidation was first reported by Adkins and Scanley2 who credited B. F. Aycock with the experimental procedure. Apparently ilycock has not published experimental details; therefore, a procedure for oxidation with chromium trioxide is included. The yields obtained by using this method are higher than those obtained by the Sandmeyer method.The Albert and Magrath3 method, using Raney nickel in ammonia, was followed for the reduction of p-cyanobenzoic acid. This method resulted in higher yields but the product contained more impurities than when the reduction was carried out using palladium in ammonia. Practically a quantitative yield of (11) (m.p. 238-240°-probably preferential preparation of cis isomer) was obtained when the aromatic nucleus was reduced in glacial acetic acid using platinum oxide as catalyst. It is interesting to note that the chemical reduction method1 for the preparation of (11) produced two forms, an a-form which softened a t 270' and a p-form which decomposed between 220-229'.The m-aminomethylcyclohexylcarboxylic acid (I) was prepared from m-tolunitrile. A chromic acid oxidation, followed by the reduction of the nitrile (1) A. . Soe., 678 (1944). 2854 (1951). group and the aromatic ring gave the new compound (I), melting point 203-204'. Acetyl derivatives of (I) and (11) were prepared and characterized for the first time, and the reduction product of p-acetamidomethylbenzoic acid was also prepared. EXPERIMENTALChromic oxide oxidation of p-tolunitrile. A solution of 35.1 g. (0.3 mole) of p-tolunitrile and 570 ml. of glacial acetic acid was placed in a 1-l., three necked flask equipped with a stirrer and a thermometer. Concentrated sulfuric acid, 45 ml., was added slody to this solution. The reaction flask was cooled to 5' and 90 g. (0.9 mole) of chromic oxide was added in small portions a t such a rate that the temperature did not rise above IO" The reaction materials were stirred a t 0-10' for 2 hr., and the temperature was then allowed to rise to 25' during an additional hour. The contents of the reaction flask were poured onto ice, and the solid products were filtered off. The crude material was dissolved in sodium carbonate, and the p-cyanobenzoic acid was precipitated vith hydrochloric acid. The purification was repea...

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