Di-t-butylethylene

Twenty years later, by studying the chlorination of cis- and trans-di-t-butylethylenes, Fahey (1966) showed that halogen bridging is a general rule. It is expected that, owing to steric repulsions between the two branched groups, the cis-alkene would prefer to react via an open / -chlorocarbocation [14] where free rotation can occur rather than via a chloronium ion [15]. 

Di-t-butylethylene [5] has one unique property in comparison with other spin traps, in that it cannot be excited under normal photolysis conditions (Amax = 185 nm). Imidyl-[5] are formed by UV photolysis of ImX-[5] solutions, and it is obvious that the mechanism must involve excitation of ImX to ImX around 205 nm, followed by either homolytic cleavage of the excited state or oxidation of [5] (Table 3) [E°(ImX /ImX ) is estimated to be very high, 6 V] to give [5] + and create conditions for inverted spin trapping. 

Cis- and ra 5-di-/-butylthiiranium tetrafluoroborates (14) and (15) were generated from cis- and tra 5-di-t-butylethylene, respectively (Scheme 7), on reaction with methyl-bis(methylthio)sulfonium tetrafluoroborate in liquid SO2 at —78 °C. Their reaction with water was studied and different reaction modes were found. ... 

The use of preformed boron hydrides is advantageous. Thus, treatment of 1,2-di-t-butylethylene with 0.5 equiv. B2H6 followed by heating the mixture for 20 h at 160-165°C gives IV ... 

Neutralization processes of ions in the radiolysis of ethane or ethylene with SFg have been shown to lead to the formation of the SF5 radical. Compounds of the type RSF5 are formed as a result of the recombination reactions with hydrocarbon radicals. A kinetic e.s.r. study of the self-reaction of SF5, and a spectroscopic and kinetic e.s.r. study of its reaction with 1,1-di-t-butylethylene, have been reported. The radical undergoes self-reaction by a second-order process and adds to 1,1-di-t-butylethylene to give BU2CCH2SF5, which decomposes by a first-order process. 

Treatment of diborane and di-t-butylethylene (trans-2,2,5,5-tetrz-methyl-3-hexene) yields an alkyldiborane that decomposes after 20 hours of heating at 160-165° C to form (LII) treatment with alkaline H2O2 gives 2,2,5,5-tetramethyl-l,4-hexanediol (65). 

Some support for this hypothesis is seen in the relatively large chemical shift differences at C-1 in cis- and trans-cyclo-octene and also in cis- and trans-di-t-butylethylene. ... 

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