THE INTRAMOLECULAR [2+4] CYCLOADDITION REACTION OF E,E-9-ANTHRYLMETHYLENE-[1-(2,5-DIMETHYL-3-FURYLETHYLIDENE)]SUCCINIC ANHYDRIDE

Red and yellow E,Z- and Z,E-isomers of the title compound isomerise photochemically or thermally to the E,E-isomer, which undergoes a [2 + 4] intramolecular cycloaddition reaction at room temperature involving the 4,5-positions of the 2,5-dimethyl-3-furyl group and the 9,10-positions of the anthryl group.