The reactions of the enolates of tert-butyl alkanoates2 and N, N-dialkylalkanamides3 with tert-butylp-tolylazo sulfide1 in THF furnish good yields of the correspondingα-p-tolylhydrazonylated esters4 and amides5. Results are reported showing the possible transformation of4 and 5 into theN-methylated derivatives8 and 9 and the subsequent deblocking of the protected carbonyl function to the corresponding
room temperature, with potassium acetoneenolate to give good yields of 1-aryl-2-propanones via spontaneous SRN1 dark reactions, α-Phenylation of pinacolone and acetophenone enolates by 1a likewise occurs in excellent yields. In agreement with the involvement of an electron-transfer catalyzed chain process, the reaction of the 4-bromo derivative 1n with pinacolone enolate gives mainly the bis-substitution
The title reaction conveniently furnishes, as the sole or main products, alpha-(p-tolylhydrazono)ketones or their N-methylderivatives (H+ or Mel quenching of the final mixture, respectively). Although the method fails with ketones having a secondary alkyl group bonded to the carbonyl, yields are otherwise more than satisfactory and particular interest is attached to the hydrazonylation of the methyl group in methyl ketones.