On the mechanism of Pd(0)-catalyzed coupling of propargylic carbonates with N-tosylhydrazones: density functional theory survey

A mechanistic investigation of the Pd-catalyzed cross-coupling betweenN-tosylhydrazones and aryl halides

“…In the final step, β-hydrogen elimination generates the aryl olefin product, and regenerates the initial palladium(0) active catalyst species. The catalytic mechanism has been studied computationally, 237,238 however reaction intermediates for this catalytic cycle have yet to be observed experimentally.…”

Overcoming Scope Limitations in Cross-Coupling of Diazo Nucleophiles by Manipulating Catalyst Speciation and Using Flow Diazo Generation

“…In contrast to the reaction with methyl 2-diazo propanoate, a stable palladium-carbene intermediate ( I4b ) was observed. No reaction barrier for phenyl group migration existed with the more stabilized diazo, which instead collapses to the benzyl Pd intermediate I5a directly following loss of nitrogen …”

Recent Advances in Transition‐Metal‐Catalyzed Reactions of N‐Tosylhydrazones

“…On the other hand, by avoiding the Bamford-Steven reaction, the rarely reported formation of N-sulfonylhydrazones has been observed. [32] One year later, Ojha et al complemented the palladium catalyzed coupling reaction of sterically hindered N-tosylhydrazones, derived from aryl ethanones, with aryl and heteroaryl halides in the absence of external ligands (Scheme 19). [33] This reaction provides a good selectivity in the presence of hydroxyl and amine functionalities.…”