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Herein, we report a ruthenium‐catalyzed redox‐neutral α‐alkylation of unsaturated alcohols based on a synergistic relay process involving olefin isomerization (chain walking) and umpolung hydrazone addition, which takes advantage of the interaction between the two rather inefficient individual reaction steps to enable an efficient overall process. This transformation shows the compatibility of hydrazone‐type "carbanions" and active protons in a one‐pot reaction, and at the same time achieves the first Grignard‐type nucleophilic addition using olefinic alcohols as latent carbonyl groups, providing a higher yield of the corresponding secondary alcohol than the classical hydrazone addition to aldehydes does. A broad scope of unsaturated alcohols and hydrazones, including some complex structures, can be successfully employed in this reaction, which shows the versatility of this approach and its suitability as an alternative, efficient means for the generation of secondary and tertiary alcohols. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed allylic alkylation of nonstabilized carbon nucleophiles is difficult and remains a major challenge. Reported here is a highly chemo‐ and regioselective direct palladium‐catalyzed C‐allylation of hydrazones, generated from carbonyls, as a source of umpolung unstabilized alkyl carbanions and surrogates of alkyl organometallic reagents. Contrary to classical allylation techniques, this umpolung reaction utilizes hydrazones prepared not only from aryl aldehydes but also from alkyl aldehydes and ketones as renewable feedstocks. This strategy complements the palladium‐catalyzed coupling of unstabilized nucleophiles with allylic electrophiles by providing an efficient and selective catalytic alternative to the traditional use of highly reactive alkyl organometallic reagents. [ABSTRACT FROM AUTHOR]