Styrene hydrochlorination

A similar mechanism was recently suggested for the hydrochlorination of styrene and t-butylethylene by Fahey and McPherson (1969). The proposed mechanistic scheme appears reasonable in a weakly dissociating solvent, such as acetic acid, although it seems somewhat surprising that the product distribution and the stereochemistry are insensitive to addition of diluents such as formic acid up to 1 1m. 

Table II shows the results for the gas-solid hydrohalogenation of the a-and fi-CD complexes with styrene at 25 C. Both the CD complexes produced racemic 8a and 9 in 30-50% yields (8a 9 = 1 1) under hydrobromination for 3 h, and no 9 but racemic 8b in 30-40% yields under hydrochlorination for 20 h.

Sigman reported a particular hydrochlorination/hydroalkoxylation reaction catalyzed by Pd(ll) in combination with Cu(ll), starting from styrenes. The first formed hydrochlorinated product in the presence of an alcohol was converted in situ to benzylic ethers [96] (Scheme 47). 

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