The α-methylenic reactions discussed in the preceding two papers recall a series of interesting observations by Baker and Nathan, which indicate that a p-methyl substituent attached to the benzene nucleus can permit electron release to the nucleus in a manner that appears only in lesser degree in higher alkyl groups, and may be absent in some (e.g., Buγ). Thus in p-methylbenzyl bromide, the suggested function of the methyl group (dotted arrows in (I) permits (see PDF for diagram) additional electron release at the C—Br bond, and so facilitates the anionization of the bromine. Baker and Nathan suggest that the electrons of the duplet constituting the C—H bond of the methyl group are less localized than those in a similarly placed C—C bond, and hence that a methyl group attached to the necessary conjugated unsaturated system is capable of electron-release by a mechanism similar to the tautomeric effect:

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