Reactions of Triarylmethyl Radicals

We have already seen that triphenylmethyl radical reacts both with itself to form Chichibabin s hydrocarbon (formula II, not the diradical) and with halogens and oxygen. The reactions of the stable radical are important because of the expectation that radicals too unstable to isolate will betray their presence by giving similar products. 

In contrast with the more reactive radicals, triphenylmethyl reacts only with the alkali metals and not with lead. 

Sodium amalgam rather than sodium is used in the preparation of triphenylmethyl from the halide the mercury prevents the formation of sodium triphenylmethyl and of Chichibabin s hydrocarbon. 

The tendency to add to systems of multiple bonds is illustrated by the following reactions  

Disproportionation by exchange of hydrogen is another common reaction  

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