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with water. The ether layer was separated, dried, and concentrated in vacuo yielding a crystalline solid which after recrystallization from benzene gave 0.04 g of pure material, mp 171-173°, whose spectral and physical properties were indistinguishable from those of tetramethylphthalyldiol prepared by another route (vide supra).

Diazonium salts of 2-amino-R'-benzophenone (R' = 4-CH3, 4-OCH3, 3-NCh) were decomposed electrolytically, thermally, and by the iodide ion. Protic and aprotic solvents were employed, with a variety of catalysts and over a range of temperatures. Using our results and published data, a general interor intramolecular oneelectron redox mechanism is proposed. Based on experimental results and theoretical calculations, this proposal alleviates many of the previously encountered difficulties in explaining the behavior of diazonium salts under varied conditions and specifically clarifies the Pschorr cyclization mechanism.Various literature surveys4-9 have revealed a long history of mechanistic studies on Pschorr-like systems. All agree that, depending on the reaction conditions, homolytic or heterolytic mechanisms, or a combination of the two, could explain the type and yield of products.(1) Contribution No. 621 from the Research Council of Alberta, Edmonton, Canada. A part of this paper was presented at the 163rd National

Pyridine and pyridine N-oxide have been phenylated by electrolytic reduction of benzenediazonium tetrafluoroborate in aprotic media giving high yields of phenylated products. Nonelectrolytic reduction systems were also investigated, leading to a new mechanism for diazonium salt-pyridine reactions. Partial rate factors and total rate ratios for pyridine iV-oxide are reported for the first time. Experimental results are related to theoretical values calculated from molecular orbital theory by Brown and Barnes.