THE ACETYL DERIVATIVE OF A NOVEL FRIES REARRANGEMENT PRODUCT

The structure of the acetyl derivative of a novel Fries rearrangement product, 8,3'-methylene[7-acetoxy-4-methyl- 2H-1-benzopyran-2-one][4'' -methyl-2''H- n-2''-one(5',6':6'',5'')-2'H-1'-benzopyran-2'-one] {IUPA C name 4-methyl-7-[(4-methyl-2,8-dioxo-2H, o[2,3-h]chromen-9-yl)methyl ]-2-oxo-2H-chromen-6-yl acetate, C26H18O8}, has been determined. The r esult confirms the somewhat surprising formation of a bis-coumarin der ivative from a coumaryl ester. The planes of the two coumarin units ar e inclined at an angle of 74.7(1)degrees with respect to one another a nd the exocyclic angles about the coumarin points of attachment to the methylene C atom show an interesting asymmetry.