REACTIONS OF ALKENEDIAZONIUM SALTS .2. METHANOLYSIS OF 2,2(2',2''-BIPHENYLYLENE)ETHENE-1-DIAZONIUM HEXACHLOROANTIMONATE - A REARRANGEMENT TO 9-METHOXYPHENANTHRENE

The title compound (1) reacts with excess methanol forming a rearranged product, 9-methoxyphenanthrene (2). 9-(Methoxymethylidene)fluorene (4) does not rearrange to give 2 under the same conditions. In deuterated methanol no labelled product is obtained, showing that the possible mechanism involves either the formation of a primary vinyl cation 5 rearranging to an aryl cation 6 or the formation of a β-alkoxycarbene (12), which rearranges to an arene. The results obtained are compared with previously reported reactions, which were postulated to proceed via a 2,2(2′,2″-biphenylylene)ethene-1-diazonium ion (23). Copyright © 1983 Verlag GmbH & Co. KGaA, Weinheim.