Abstract
Stable derivatives of oxaphosphaphenanthrenes were prepared by using the reactions of dialkyl acetylenedicarboxylate with 3-bromo-2-naphthol in the presence of trimethyl or triphenyl phosphite under microwave conditions at 70 °C in good yields. Under similar conditions, chromene derivatives were produced by using triethyl phosphite and dialkyl acetylenedicarboxylate in the presence of OH-acids in excellent yields
Keywords: 4-hydroxycoumarine, acetylenic compounds, chromenes, one-pot reactions, trimethyl phosphate, triphenyl phosphite.