Photosolvolysis of 2-Allylated Anilines to 2-Indanols

Article abstract of DOI:10.1002/hlca.19860690122

It is shown that 2-allylated anilines (cf.Schemes 2-4,7, and 8) on irradiation in protic solvents such as H2O.MeOH, and EtOH in the presence of H2SO4 undergo a novel photosolvolysis reaction to yield specifically trans-2-hydroxy- and trans-2-alkoxy-1-methylindanes.Intermediates are presumably tricyclo<4.3.0.0^1,8>nona-2,4-dienes formed in an intramolecular <2s+2s> cycloaddition reaction (cf.Scheme 7).On the other hand, N,N,N-trimethyl-2-(1'-methylallyl)anilinium salts 18 (Scheme 6) and 2-(3'-butenyl)-N,N-dimethylaniline (17) lose on irradiation in MeOH or H2SO4/MeOH the ammonium group reductively to yield (1-methylallyl)benzene (19) and 1-methylindane (20), respectively.