Collect. Czech. Chem. Commun. 1989, 54, 2425-2432

Preparation of unsymmetrically substituted Stenhouse salts

Peter Šafář and Jaroslav Kováč

Department of Organic Chemistry, Slovak technical University, 813 37 Bratislava


Unsymmetrically substituted Stenhouse salts IVa-IVj (iminium salts of 1-phenylmethylamino-5-(4-X-phenylamino)-2-hydroxy-2,4-pentadienal) arise by reaction of N-2-furfurylidene-N-phenylmethyliminium perchlorate (V) with substituted anilines. Primary and secondary aliphatic amines do not react in this way. Unsymmetrically substituted Stenhouse salts are also formed from iminium salt of 1,5-di(phenylmethylamino)-2-acetoxy-2,4-pentadienal (IV) by nucleophilic substitution with aromatic and aliphatic amines.