a. Explain why the alkyl halide shown here reacts much more rapidly than do primary alkyl halides,

Question:

a. Explain why the alkyl halide shown here reacts much more rapidly than do primary alkyl halides, such as butyl chloride and pentyl chloride, with guanine residues.

b. The alkyl halide can react with two guanine residues in two different chains, thereby cross-linking the chains. Propose a mechanism for the cross-linking reaction.