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Photolysis of the azo-precursors of 2,3- and 1,8-naphtoquinodimethane. Preliminary communication

✍ Scribed by Markus Gisin; Jakob Wirz

Publisher
John Wiley and Sons
Year
1976
Tongue
German
Weight
291 KB
Volume
59
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

A novel oxidation method for the synthesis of labile azo‐alkanes is reported. Matrix‐isolated 2,3‐naphthoquinodimethane is obtained by photolysis of 1,4‐dihydrobenzo[g]‐phthalazine in a rigid matrix (EPA glass) at 77 K and the electronic structure of its ground and lowest excited states is discussed. Nitrogen elimination from 1,4‐dihydronaphtho[1,8‐de][1,2]‐diazepine to yield acenaphthene occurs exclusively upon ππ* excitation while irradiation in the n‐π* absorption region induces cis/trans isomerization of the azo‐moiety. Neither ns flash nor low‐temperature photolysis provide evidence for the occurrence of 1,8‐naphthoquinodimethane as an intermediate in the formation of acenaphthene.

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