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Vol. 81 priate acid chloride. The mixture was cooled, solvents evaporated almost to dryness in vacuo; water added and the gum triturated and washed with excess water yielding the desired compound in the form of its hydrochloride. Conversion of the crude salt to the free base was accomplished by slurrying in methanol solution for 10 minutes with an equal weight of silver carbonate. After filtration from silver salts and evaporation of the methanol the ester was crystallized from one of the solvents listed in B.

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Various reagents have been used in the past for the oxidation of formazans to the corresponding tetrazolium salts. These include yellow mercuric oxide,' lead tetraacetate12 hydrogen peroxide and hydrochloric acid in the presence of vanadium pent-oxide3 and nitric acid.4While t-butyl hypochlorite usually functions as a chlorinating agent, a few oxidation reactions have been reported. Clark5 found that primary alcohols can be oxidized to the corresponding aldehydes. Similarly, while studying chlorination of various aromatic aldehydes Ginsberg6 found that certain ring substituents favored conversion of the aldehyde to the corresponding acid chloride rather than ring chlorination.This note reports the results of several experiments in which t-butyl hypochlorite was used as the oxidizing agent in the preparation of tetrazolium chlorides from formazans. SubstantiallyCsHa-C I el 4-(CH,),COH equimolar quantities of t-butyl hypochlorite and formazan are required for the oxidative conversion, which is carried out in an inert solvent. The presence of small amounts of an acidic or basic catalyst appears to increase the reaction rate but is not essential. Experimental 2,3,5-Triphenyltetrazolium Chloride.-Triphenplfortnazan (6.0 g., 0.02 mole) is dissolved in 100 nil. of chloroform, a few ml. of alcoholic potassium hydroxide added and the mixture chilled t o 5 " . t-Butyl hypochlorite (8 ml. of 33% material, 0.023 mole) is added dropwise with stirring. The color changes from opaque t o a clear red but is not completely discharged. T h e solution is filtered, evaporated on the steam-bath t o about 15 cc., and acetone and ether added. The precipitate formed is filtered off, dissolved in chloroform containing 1 or 2 drops of alcohol and precipitated with a little ether. Four grams of product is obtained (60% yield). Anal. Calcd.: K, 16.74; CI, 10.59. Found: N, 16.6; CI, 10.7. 5-n-Hexyl-2,3-diphenyltetrazolium Chloride.-Impure C-n-hexyl-X,T\"-diphenylformazan (4 g., 0.013 mole) is dissolved in 50 ml. of chloroform and the mixture chilled t o 5 " . t-Butyl hypochlorite (0.013 mole) is added dropwise with stirring. The solution is evaporated on the steambath. Ether and acetone are added and the resulting pre-\N-iY-CeH5(1) H. v.