Unexpected reaction of 2-amino-1,4-naphthoquinone with aldehydes Universiteit Antwerpen
Treatment of 3-substituted 2-amino-1,4-naphthoquinones 3 with an aldehyde in a solution of hydrobromic acid in acetic acid led to 2,4-disubstituted naphtho[2,1-d]oxazol-5-ols. The outcome of this simple conversion is even more remarkable in view of the very similar reactions reported in literature, which all give rise to completely different products. Furthermore, the acquired naphthoxazoles 511 could be oxidatively ring opened by means of PIFA ...