Highly Efficient Copper-Catalyzed Synthesis of Internal Alkynes<i>via</i>Aerobic Oxidative Arylation of Terminal Alkynes
作者:Honghua Rao、Hua Fu、Yuyang Jiang、Yufen Zhao
DOI:10.1002/adsc.200900723
日期:2010.2.15
We have developed a novel and highlyefficient, copper-catalyzed synthesis of internal alkynes via oxidative couplings of aromatic boronic acids with terminalalkynes at room temperature. The protocol uses inexpensive copper(I) oxide [Cu2O] as the catalyst, oxygen in the air as the stoichiometric oxidant; no ligand and sealed reaction vessels are required, and remarkable functional group tolerability
Recyclable heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes: Practical access to vicinal tricarbonyls
作者:Wenli Hu、Bin Huang、Bingbo Niu、Mingzhong Cai
DOI:10.1016/j.tetlet.2021.152953
日期:2021.3
A highly efficient heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes has been developed using 2,6-dichloropyridine N-oxide as the oxidant in dichloromethane (CH2Cl2) at room temperature, providing a novel and practical approach for the construction of diverse vicinal tricarbonyls such as α,β-diketoesters, 1,2,3-triketones, and α,β-diketoamides in good to excellent yields. The heterogeneous
Borane-catalyzed cascade Friedel–Crafts alkylation/[1,5]-hydride transfer/Mannich cyclization to afford tetrahydroquinolines
作者:Bei-Bei Zhang、Shuo Peng、Feiyi Wang、Cuifen Lu、Junqi Nie、Zuxing Chen、Guichun Yang、Chao Ma
DOI:10.1039/d1sc05629h
日期:——
An unprecedented redox-neutral annulation reaction of tertiary anilines with electron-deficient alkynes was developed that proceeds through a cascade Friedel–Crafts alkylation/[1,5]-hydride transfer/Mannich cyclization sequence. Under B(C6F5)3 catalysis, a range of functionalized 1,2,3,4-tetrahydroquinolines were facilely constructed in moderate to good yields with exclusive 3,4-anti-stereochemistry
A novel palladium-catalyzed, one-pot, four-step cascademethod has been developed to afford functionalized gamma-lactones in moderate to good yields. This novel and general methodology represents a rare instance of carbonylation of the C(sp(3))-palladium bond.
Transition-metal-free C–C bond cleavage and formation: efficient synthesis of 2,3-diarylimidazo[1,2-α]pyridines from 2-aminopyridines and alkynoates
作者:Zhengwang Chen、Yuelu Wen、Guotian Luo、Min Ye、Qinghao Wang
DOI:10.1039/c6ra19291b
日期:——
A highly efficient transition-metal-free cyclization reaction for the synthesis of 2,3-diarylimidazo[1,2-α]pyridines is described. A variety of substituted 2-aminopyridines and alkynoates are compatible under the standard conditions. This protocol is marked by the cleavage of a C–C bond and the formation of a new Csp2–Csp2 bond under transition-metal-free conditions.