No abstract

BASICITIES OF AZOXYBENZENES 949 p-isomers give identically quantitative yields of the same compound. I n the 4-methoxy compounds, the yields are neither quantitative nor equal, but apparently, judging from the spectra obtained, the other products are not hydroxymethoxyazobenzenes. Probably side reactions occurring a t different rates complicate the reaction. The findings thus seem to confirm the Russian workers proposed mechanism involving a threemembered ring i~~t e r m e d i a t e .~The most unexpected finding is that, whereas the oxygen atom migrates to the free p-position in both the 4-bromo-and 4-methoxy compounds, it migrates to an o-position (in the unsubstituted ring) in the 4-methyl compound. This is even more surprising since the electronic effect of the methyl group is generally considered intermediate between the bromo and methoxy groups. No explanation for this surprising finding can be offered at this time. It is conceivable that minor differences in reaction conditions give rise to the observed differences in behavior. This possibility, however, is extremely unlikely because the reactions are so clean, giving no indication that mixtures are obtained. The question is being investigated further.

No abstract

ChemInform Abstract 1,1-Diphenylethylene (Ia) undergoes radical-induced dimerization in the presence of aminium hexachloroantimonates to give the indan (II). Addition of water to the reaction mixture results in the formation of the tetraphenylbutadiene (IIIa) and the tetrahydrofuran (Va). The analogous reaction with (Ib) -(Id) yields (IIIb) -(IIId) and the tetraarylcyclobutanes (IVc) and (IVd).

1 u11 Kinetics of the Formation of Dibenzotetraazapentalenes.