A Convenient Synthesis of a Simple Coumarin from Salicylaldehyde and Wittig Reagent (I): A Synthesis of Methoxy- and Hydroxycoumarins

Article abstract of DOI:10.3987/COM-94-S(B)54

Reaction of methoxy- and hydroxysalicylaldehydes (1) with phosphorane in diethylaniline under reflux gave only coumarins (3) in high yields except for 3-methoxysalicylaldehyde (1b).It was clarified that methoxy group(s) at C4 and C6 on 1 facilitated the formation of 3.