Methano-Bridged 14?-Electron Aromatic Annulenes. 2. 5-Methoxy-7,12-methano-6-azabenzannulene and the Benzenesulfonate Ester of 5-Hydroxy-7,12-methano-6-azabenzannulene

Article abstract of DOI:10.1021/jo00327a008

The syntheses of 5-methoxy-7,12-methano-6-azabenz<10>annulene (4) and the benzenesulfonate ester of 5-hydroxy-7,12-methano-6-azabenz<10>annulene (5) are described.Compounds 4 and 5 were shown to be delocalized aromatic systems as evidenced by their 13C and 1H NMR chemical shifts.Ester 5 was prepared by Beckmann rearrangement of 7a (which was available from anion 6 by treatment with tert-butyl nitrite).Hydrolysis of 5 with potassium hydroxide followed by alkylation with trimethyloxonium tetrafluoroborate gave the benz<10>annulene 4.