A chelation-assisted palladium-catalyzed C═Cbond cleavage of α, β-unsaturated ketone to form alkenyl nitrile in the presence of nitrile is disclosed on the basis of a formal group-exchange reaction formulated as C1═C2 + C3 → C1═C3 + C2, differing from normal alkene oxidative cleavage and metathesis type. The isolated key active Pd(II) complex as well as deuterium-labeled experiment revealed the necessity
α的螯合辅助钯催化的C = C键的断裂,β不饱和酮向腈的存在形式烯腈,公开了一种正式基交换反应的配制为C的基础上,1 = C 2 + C 3 →C 1 = C 3 + C 2,从正常烯烃氧化裂解和复分解型不同。分离出的关键活性 Pd(II) 配合物以及氘标记实验揭示了螯合基团的必要性,并提出了一条合理的催化途径。
Brønsted acid mediated nitrogenation of propargylic alcohols: an efficient approach to alkenyl nitriles
作者:Xiaoqiang Huang、Ning Jiao
DOI:10.1039/c4ob00888j
日期:——
A novel and efficient approach to alkenyl nitriles from readily available propargylic alcohols has been developed. This nitrogenation reaction is transition-metal-free and could be conducted under air at ambient temperature, which makes this protocol promising and practical. Moreover, NH4Br is disclosed as an efficient additive to promote the stereoselectivity of this reaction.
Rhodium(III)-Catalyzed Oxadiazole-Directed Alkenyl C–H Activation for Synthetic Access to 2-Acylamino and 2-Amino Pyridines
作者:Fan Yang、Jiaojiao Yu、Yun Liu、Jin Zhu
DOI:10.1021/acs.joc.7b01303
日期:2017.10.6
We report herein a Rh(III)-catalyzed alkenyl C–H activation protocol for the coupling of oxadiazoles with alkynes and synthesis of 2-acylamino and 2-amino pyridines, an important heterocyclic scaffold for various naturals products and synthetic pharmaceuticals bearing a readily reacting functional group. The selective protection/deprotection of amino groups through simple solvent switching, good functional
Iron-Facilitated Direct Oxidative C−H Transformation of Allylarenes or Alkenes to Alkenyl Nitriles
作者:Chong Qin、Ning Jiao
DOI:10.1021/ja1070202
日期:2010.11.17
facilitated by an inexpensive homogeneous iron catalyst. Three C-H bondcleavages occur under the mild conditions during this process. Mechanistic studies indicate that the cleavage of the allyl C(sp(3))-Hbond is involved in the rate-determining step. This observation may provide an opportunity to achieve C(sp(3))-H functionalization catalyzed by an iron catalyst.