A GENERAL SYNTHETIC METHOD OF 1,2-DIHYDROCYCLOBUTACOUMARIN AND ITS 1-SUBSTITUTED DERIVATIVES

Article abstract of DOI:10.1246/cl.1981.423

4-Methoxycoumarin reacts photochemically with ethylene and its substituted derivatives to form 8b-methoxy-1,2,2a,8b-tetrahydro-cyclobutacoumarin and its 1-substituted derivatives, which in turn eliminate methanol by boron trifluoride etherate in benzene to give the corresponding 1,2-dihydrocyclobutacoumarins in high overall yields.