Immediately upon mixing ICls and 2, 3-dimethyl-2-butene in CCl4 at 25° C a new absorption band due to an alkene-ICl molecular complex appears at 295±5 nm and decreases rapidly with time. The rate law under conditions of (alkene) 0 (ICl) 0 for the electrophilic addition of ICl to 2, 3-dimethyl-2-butene, E-and Z-2-butene, and E-and Z-1-phenylpropene is-d (ICl)/dt= kexpt (alkene)(ICl) 3/{1+ kAD (alkene)} 3 where K AD is the equilibrium constant for the ...
