The limitations of present methods of synthesizing 1,2-diallcylhytlrazi~~es are discussed. A new method of obtaining these colllpounds in good yields by the reduction of azines with lithium aluminum hydride is reported. Lithium a l u m i n~~m deuteride was employed as a tracer to investigate the mechanism oi the reaction. The 1,2-dialkylhydrazines were oxidized to the azoparaffins in over 90% yields by mercuric oxide in water. INTRODUCTIONAn important source of free radicals for kinetic investigations is the thennal or photochemical decomposition of azoalkanes (11). Up to now the availability of these compounds has been limited on account of the difficulty of obtaining the 1,2-dialkylhydrazines. For example, of the lower azoalltanes only the methyl and isopropyl compounds have long been known, azoethane having been prepared quite recently (15). This work was undertaken t o develop a general method of preparing 1,2-dialkylhydrazines and thereby to provide a route to the required azocompounds.Knorr and Icohler (9) obtained 1,2-dimethylhydrazine by alltaline hydrolysis of dimethylpyrazole and characterized it by means of several derivatives. I t had previously been prepared by Harries and I

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October I979for instance, we observed that the proton backscatter yield off a thin Au film is the same as that off an identical film with a thin surface layer of carbon. Accordingly, corrections to Eq. [A-3J or [A-4] due to charge exchange effects are negligible.

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Measurements of vicinal H—N—C—H coupling constants in the conjugate acids of two tertiary amines having known rigid conformations provide support for the validity of the Karplus relation for this type of coupling constant. Seven vicinal coupling constants agree to within 0.5 Hz with those calculated from the expression [Formula: see text].