A mild and highly efficient Cu‐catalyzed cascade cyclization/thiocyanation of unactivated alkenes bearing hydrazones has been developed. A broad range of SCN‐substituted pyrazolines have been readily obtained in good to excellent yields with commercially available and very cheap Cu(acac)2 and NH4SCN. This present method provides a rapid, facile, and practical access to valuable pyrazolines with the
Oxy‐/Amino‐Difluoromethylthiolation of Alkenes: Synthesis of HCF<sub>2</sub>S‐Containing Isoxazolines and Pyrazolines
作者:Xin Chen、Yun‐Tao Shen、Zhi‐Wei Zhao、Yu‐Jian Hou、Bo‐Xun Sun、Tai‐Gang Fan、Ya‐Min Li
DOI:10.1002/adsc.202200672
日期:2022.9.20
Oxy-/amino-difluoromethylthiolation of β,γ-unsaturated oximes/hydrazones have been developed for construction of HCF2S-containing isoxazolines and pyrazolines by employing PhSO2SCF2H as difluoromethylthiolation reagent under mild conditions. Such transformations exhibit good functional group tolerance and scalability. Possible mechanisms are proposed.
β,γ-不饱和肟/腙的氧-/氨基-二氟甲基硫醇化已被开发用于在温和条件下使用PhSO 2 SCF 2 H 作为二氟甲基硫醇化试剂来构建含HCF 2 S 的异恶唑啉和吡唑啉。这种转换表现出良好的官能团耐受性和可扩展性。提出了可能的机制。
Synthesis of Dihydropyrazoles via Pd‐Catalyzed Heterocyclization/Carbonylation Reaction: Development and Parameterization Studies
作者:Amanda A. Barboza、Juliana A. Dantas、Guilherme A. M. Jardim、Attilio C. Neto、Willian X. C. Oliveira、Tobias Gensch、Marco A. B. Ferreira
DOI:10.1002/cctc.202200894
日期:2022.10.21
Pd-catalyzed heterocyclization/carbonylation cascade reaction encompassing the formation of 3 new bonds is described, affording dihydropyrazole-esters in moderate to excellent yields and good functional group tolerance. Optimization was carried out along with a phosphine/base parameterization study, providing important structure-reactivity insights for pyridine-bases, mono- and bisphosphines.