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The preparation of a tetrazole derivative containing the acetyl group as a functional component was first reported by Harvill, Herbst, and Schreiner (1) who converted several l-substituted-5-haloalkyltetrazoles into the corresponding hydroxyalkyl derivatives through the intermediate acetoxyalkyl compounds. One of these tetrazoles, 1 -cyclohexyl-5-(1 -hydroxyethyl)tetrazole, was oxidized in aqueous solution with potassium dichromate and sulfuric acid to 1-eyclohexyl-5-acetyltetrazole. However, no further reactions of this compound were reported by the authors.Harvill also reported the synthesis of 1 -phenyl-5-(1 -hydroxyethyl)tetrazole in the same manner but did not oxidize this derivative to the ketone.In this laboratory, 1 -phenyl-5-acetyltetrazole (VII) has been prepared by means of the synthetic route shown in Figure I, which contains a variation in the method used by Harvill.Previous to the publication of Harvill attempts in this laboratory to prepare l-phenyl-5-(l-hydroxyethyl)tetrazole (VI) from 1 -phenyl-5-(1 -chloroethyl)tetrazole through the intermediate acetoxy derivative met with little success and gave at best only very low yields. However, it was found that l-phenyl-5-(1 -chloroethyl)tetrazole reacted readily with sodium methoxide in refluxing methanol to give 1 -phenyl-5-(1 -methoxyethyl) tetrazole (V). This ether was split by refluxing it with 48 % aqueous hydrobromic acid, methyl bromide being evolved and 1 -phenyl-5-(1 -hydroxyethyl)tetrazole being isolated in good yields. However, 32 % aqueous hydrobromic acid had no effect on the methyl ether in the same length of time.

A method has been developed for the synthesis of 5-substituted-l-tetrazolylacetic esters and acids and a series of these compounds has been prepared. Several l-substituted-5-tetrazolylacetic acids have also been prepared by this method but substituted tetrazolylcarboxylates could not be isolated. Some comparative properties of the 1-and 5-tetrazolylacetic acids are briefly discussed.

The preparation of l-phenyl-5-chloromethyltetrazole (I) was first disclosed in a patent (1) issued to Harvill and Herbst covering the preparation of 1-substituted-5-a-halogen alkyltetrazoles. In a more recent publication (2) these authors report the preparation of a wide variety of -haloalkyltetrazoles and the reaction of these compounds with various reagents to give amino and hydroxy derivatives. They state that the 5-haloalkyltetrazoles react like typical alkyl halides. This observation has been generally substantiated in an investigation of a number of reactions of l-phenyl-5-chloromethyltetrazole in this laboratory.Although the structure of l-phenyl-5-chloromethyltetrazole together with its irritant action on the skin may suggest analogies with compounds of the benzyl chloride type, such a comparison does not appear to be valid. This tetrazole reacts immediately with sodium iodide in acetone solution, precipitation of sodium chloride being essentially complete in less than one minute. In comparison, several minutes reflux of this compound in alcoholic silver nitrate solution gave no evidence of silver chloride precipitation. These results indicate

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