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Improved syntheses of 6‐hydroxy‐5‐methoxy‐ and 5‐hydroxy‐6‐methoxyindoles and their O ‐acetates, analogs of natural eumelanin precursors
Author(s) -
Rogers C. Bradford,
Blum Charles A.,
Murphy Bryan P.
Publication year - 1987
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570240410
Subject(s) - chemistry , nitromethane , nitration , vanillin , organic chemistry , syringaldehyde
Improved routes for syntheses of gram quantities of the isomeric 5,6‐acetoxymethoxyindoles, and milligram amounts of the 5,6‐hydroxymethoxyindoles, have been developed. They depend on regiospecific nitration of the benzyl ethers of vanillin and isovanillin as the first steps. Improved condensations of 4,5‐acetoxymethoxy‐2‐nitrobenzaldehydes with nitromethane gave 4,5‐acetoxymethoxy‐2,β‐dinitrostyrenes as the key intermediates to all four indoles.