Kinetics of [2 + 2] cycloadditions of 2,2-bis(trifluoromethyl)ethylene-1,1- dicarbonitrile with enol ethers, 1,1-dimethylbutadiene, and allytrimethylsilane

Article abstract of DOI:10.1016/0040-4039(90)80124-5

The rate constant with ethyl vinyl ether is enhanced by α-donor substituents whereas β-methyl groups strongly retard by steric hindrance. The title compound (BTF) is 2400 times more active than TCNE towards ethyl vinyl ether in benzene. The rates of the title reactions increase 70- to 2300-fold with solvent polarity.