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Updated: Sep 20, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
A base-dependent reactivity switch in Baylis-Hillman ketones: access to N'-alkyl benzohydrazides and fluorescent
Sachin Sharma1, Ajit Kumar Jha1, Suman Kumawat1
1Department of Chemistry, School of Chemical Sciences and Pharmacy, Central University of Rajasthan, NH-8, Bandarsindri, Distt. Ajmer, Rajasthan-305817, India. easwar.srinivasan@curaj.ac.in.
Abstract:
A switch in the reactivity of Morita-Baylis-Hillman (MBH) ketones was observed upon interaction with hydrazines in the presence/absence of a base. The addition of NEt3 brought about an insertion of hydrazine into the MBH ketone skeleton, resulting in the formation of benzohydrazides; whereas in the absence of a base, a concomitant aza-Michael addition/condensation led to the formation of strongly fluorescent dihydropyrazoles, which could be further oxidized to aromatic pyrazoles.
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