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。
Chiral-at-Metal Rh(III) Complex-Catalyzed Decarboxylative Michael Addition of β-Keto Acids with α,β-Unsaturated 2-Acyl Imidazoles or Pyridine
作者:Shi-Wu Li、Jun Gong、Qiang Kang
DOI:10.1021/acs.orglett.7b00220
日期:2017.3.17
chiral-at-metal Rh(III) complex-catalyzed, highly efficient enantioselective decarboxylative Michaeladdition of β-keto acids with α,β-unsaturated 2-acyl imidazoles or pyridine has been developed, affording the corresponding adducts in 94–98% yield with up to 96% enantioselectivity. This protocol exhibits remarkable reactivity, as the complex with a Rh(III) loading as low as 0.05 mol % can catalyze the decarboxylative
1-Acetyl-3,5-diaryl-4,5-dihydro(1<i>H</i>)pyrazoles: Exhibiting Anticancer Activity through Intracellular ROS Scavenging and the Mitochondria-Dependent Death Pathway
作者:Jimi M. Alex、Sandeep Singh、Raj Kumar
DOI:10.1002/ardp.201400199
日期:2014.10
5‐dihydro(1H)pyrazoles (JP‐1 to JP‐17) bearing two aromatic rings at positions 3 and 5, either of which ought to be heterocyclic, were synthesized and evaluated for their anti‐proliferative potential against breast cancer (MCF‐7 and T‐47D) and lung cancer (H‐460 and A‐549) cell lines for the first time. JP‐1–7, ‐10, ‐11, ‐14, and ‐15 were observed to exhibit significant anti‐proliferative activity against
Dialkyl Phosphite-Initiated Cyclopropanation of α,β-Unsaturated Ketones Using α-Ketoesters or Isatin Derivatives
作者:Deng Yin、Hui Liu、Chong-Dao Lu、Yan-Jun Xu
DOI:10.1021/acs.joc.6b03009
日期:2017.3.17
cyclopropanation of α,β-unsaturatedketones using α-ketoesters or isatin derivatives is reported. The cyclopropanation reaction occurs via a cascade transformation that starts with addition of deprotonated dialkyl phosphite to the keto groups of α-ketoesters or isatin derivatives, followed by [1,2]-phosphonate/phosphate rearrangement to generate α-phosphonyloxyenolate intermediates, which are trapped by α,β-unsaturated
polycyclization of oxotriphenylhexanoates. The polycyclization is governed by electronic effects, and three major synthetic paths have been established leading to stereochemically complex tricyclic frameworks with up to five stereogenic centers. The method is compatible with an array of functional groups, allowing pharmacophoric elements to be introduced post cyclization.
One-Pot Reactions for Modular Synthesis of Polysubstituted and Fused Pyridines
作者:Zhidong Song、Xin Huang、Wenbin Yi、Wei Zhang
DOI:10.1021/acs.orglett.6b02883
日期:2016.11.4
3-dicarbonyl-initiated one-pot Michael addition/[5 + 1] annulation/dehydrofluorinative aromatization reaction sequence is introduced for regioselectivesynthesis of di-, tri-, tetra-, and pentasubstituted pyridines as well as fusedpyridines. This simple and modular synthesis is performed using readily available starting materials and under transition-metal catalyst-free conditions.