Aspects of the metallic halide-catalysed reaction of Grignard reagents with organic halides. Part IV. Products formed with phenylalkyl bromides

Abstract

Phenylalkyl radicals are formed in the cobalt(II) chloride-catalysed reaction of methylmagnesium iodide with benzyl bromide, phenethyl bromide, 3-phenylpropyl bromide, and 4-phenylbutyl bromide. The radicals all form products by substitution in benzene used as diluting solvent. Additionally 4-phenylbutyl radicals undergo internal cyclisation to form tetralin. With the benzyl and phenethyl radicals, but not 3-phenylpropyl and 4-phenylbutyl radicals, dimerisation products are also formed. When benzylidene bromide is used as halide the major product is trans-stilbene.