Ethylmagnesium bromide, reaction with acetophenone

In 1964, thanks to the development of modern techniques, especially electron-spin resonance (ESR), a direct proof could be given of the occurrence of radicals in the reaction of Grignard reagents, such as ethylmagnesium iodide, phenylmagnesium bromide, and /Jflra-tolylmagnesium bromide, in tetrahydrofuran (THF) with aromatic ketones, such as 4-chlorobenzophenone, 4-aminobenzophenone, 4-methoxybenzophenone, 4,4 -dimethoxybenzophenone, acetophenone, and 4-bromoacetophenone [34]. 

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