The Diels-Alder reactions of N-phenylmaleimide and dimethyl acetylenedicarboxylate with benzene oxide (1, 3, 5-cyclohexatriene 1, 2-oxide, 3) and its more substituted derivatives 1, 2-dimethyl-1, 3, 5-cyclohexatriene 1, 2-oxide (7) and 10-oxatricyclo [4.3. 1.0] deca-2, 4-diene (11) in a kinetic manner gave exclusively products of addition anti to the plane- nonsymmetrical oxygen. The structures of the adducts were determined unequivocally by ...
![1,6-dimethyl-7-oxabicyclo[4.1.0]hepta-2,4-diene结构式](https://image.chemsrc.com/caspic/269/73654-32-7.png)
![1,6-dimethyl-7-oxabicyclo[4.1.0]hept-3-ene结构式](https://image.chemsrc.com/caspic/041/57338-10-0.png)