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1.
Copper(I)‐Catalyzed Interrupted Click Reaction: Synthesis of Diverse 5‐Hetero‐Functionalized Triazoles 下载免费PDF全文
Weiguo Wang Xianglong Peng Fang Wei Prof. Chen‐Ho Tung Prof. Zhenghu Xu 《Angewandte Chemie (International ed. in English)》2016,55(2):649-653
The 5‐heterofunctionalized triazoles are important scaffolds in bioactive compounds, but current click reactions (CuAAC) cannot produce these core structures. A copper(I)‐catalyzed interrupted click reaction to access diverse 5‐functionalized triazoles is reported. Various 5‐amino‐, thio‐, and selenotriazoles were readily assembled in one step in high yields. The reaction proceeds under mild conditions with complete regioselectivity. It also features a broad substrate scope and good functional group compatibility. 相似文献
2.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(35):10612-10616
A copper(I)‐catalyzed interrupted click reaction in the presence of trifluoroacetic anhydride has been developed, wherein an N‐trifluoroacetyl group is used to accelerate the ring‐opening of the putative 5‐copper(I) triazolide intermediate. Under the optimized reaction conditions, a broad range of azides and alkynes were found to participate in this transformation, thus affording 3‐trifluoromethyl‐substituted 1,2,4‐triazinones in moderate to excellent yields. The reaction has proven to be compatible with a variety of electron‐withdrawing and electron–donating groups, halogens, and nitrogen‐ and sulfur‐containing heterocycles, as well as pharmaceutically relevant molecules. 相似文献
3.
Cu(I)‐Catalyzed Regioselective and Highly Efficient One‐Pot Synthesis of Novel 1,2,3‐Triazoles Decorated with Pyridine and Heterocyclic Amines 下载免费PDF全文
Khushbu Kushwaha Monika Vashist Mahesh Chand Subhash C. Jain 《Journal of heterocyclic chemistry》2016,53(4):1106-1112
An efficient one‐pot synthesis of 1,2,3‐triazoles via the three‐component coupling reaction between propargyl bromide, secondary amines, and 3‐azidopyridine in the presence of CuI as catalyst has been presented. The reaction is highly regioselective and afforded novel 1,4‐disubstituted‐1,2,3‐triazoles in excellent yields by the [3 + 2] Huisgen cycloaddition reaction. This method avoids isolation and handling of terminal acetylenes. The ease of purification has made this methodology clean and safe for the synthesis of 1,2,3‐triazoles with a broad scope. 相似文献
4.
IrIII‐Catalyzed One‐Pot Cascade Synthesis of Pentacyclic‐Fused Carbazoles from Indoles and Diazoes 下载免费PDF全文
Shuai‐Shuai Li Ying‐Qi Xia Fang‐Zhi Hu Chen‐Fei Liu Fu Su Prof. Dr. Lin Dong 《化学:亚洲杂志》2016,11(22):3165-3168
A highly efficient IrIII‐catalyzed cascade cyclization of indoles and diazoes giving access to unique pentacyclic‐fused carbazoles has been developed. This novel strategy expanded the application scope of coupling partners to take diazo compounds as a C2 source, and two new cycles, three new C?C and one new C?N bonds were formed in one‐pot. 相似文献
5.
Dr. Kaushik Chanda Sourav Rej Prof. Dr. Michael H. Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(47):16036-16043
We report the highly facet‐dependent catalytic activity of Cu2O nanocubes, octahedra, and rhombic dodecahedra for the multicomponent direct synthesis of 1,2,3‐triazoles from the reaction of alkynes, organic halides, and NaN3. The catalytic activities of clean surfactant‐removed Cu2O nanocrystals with the same total surface area were compared. Rhombic dodecahedral Cu2O nanocrystals bounded by {110} facets were much more catalytically active than Cu2O octahedra exposing {111} facets, whereas Cu2O nanocubes displayed the slowest catalytic activity. The superior catalytic activity of Cu2O rhombic dodecahedra is attributed to the fully exposed surface Cu atoms on the {110} facet. A large series of 1,4‐disubstituted 1,2,3‐triazoles have been synthesized in excellent yields with high regioselectivity under green conditions by using these rhombic dodecahedral Cu2O catalysts, including the synthesis of rufinamide, an antiepileptic drug, demonstrating the potential of these nanocrystals as promising heterogeneous catalysts for other important coupling reactions. 相似文献
6.
José Barluenga Prof. Dr. Abraham Mendoza Félix Rodríguez Dr. Francisco J. Fañanás Dr. 《Angewandte Chemie (International ed. in English)》2009,48(9):1644-1647
Functionalized spiroacetals have been easily prepared in a one‐pot three‐component coupling process that involves the reaction of pentynol derivatives, salicylaldehydes, and amines in the presence of catalytic amounts of a palladium(II) complex (see scheme). Alternatively, oxygen‐substituted spiroacetals can be obtained by using orthoesters as the third component.
7.
Maryam Ciyabi Hashjin Roghayeh Ciyabi Maryam Baharloui Ghaffar Hosseini Hamed Tavakoli 《中国化学》2012,30(2):223-227
In this work, readily prepared copper supported on the SiO2 nanoparticles has been found to effectively catalyze the 1,3‐dipolar cycloaddition of a variety of azides, alkynes, epoxides and sodium azide, furnishing the corresponding 1,2,3‐triazoles and β‐hydroxytriazoles. Click reaction proceeds in short reaction times and under mild reaction conditions, and the resulting products are obtained in good yields at ambient temperature. 相似文献
8.
《中国化学》2017,35(8):1239-1245
An efficient and green copper(II ) acetylacetonate‐catalyzed protocol for the Huisgen‐click reaction in water at 100 °C has been established. The protocol was not only suitable for the reaction between organic azides and alkynes, but also suitable for one‐pot three‐component reaction among alkyl halides, NaN3 and alkynes. 相似文献
9.
1‐Monosubstituted aliphatic 1,2,3‐triazoles were synthesized by a one‐pot reaction from aliphatic halides (Cl and Br), sodium azide and propiolic acid. The yields ranged from moderate to good. The reaction was easily carried out in DMF with Cs2CO3 at 100°C by copper‐catalyzed click cycloaddition/decarboxylation. 相似文献
10.
The synthesis of a series of 3,5‐disubstituted isoxazole‐4‐carboxylic esters containing N‐substituted 1,2,3‐triazoles ( V ) starting from various benzaldehydes ( I ) is reported. Benzaldehydes undergo oximation with hydroxylamine hydrosulfate. Later, chlorination followed by condensation with methylacetoacetate and the hydrolysis of the resulting ester afforded respective carboxylic acid ( II ), which on chlorination with PCl5 gave the corresponding acid chlorides ( III ). The coraboxylic acid chlorides ( III ) on propargylation gave propargylic esters ( IV ) and these on click reaction gave the title compounds ( V ). 相似文献
11.
Four‐Component,One‐Pot Synthesis of 1,4‐Disubstituted 1,2,3‐Triazoles Bearing 1‐(2‐Phenylselenocyclohexyl) Group 下载免费PDF全文
Wusheng Sheng Shouri Sheng Jiangbo Zeng Zhenzhong Huang Mingzhong Cai 《Journal of heterocyclic chemistry》2014,51(Z1):E222-E226
An efficient, one‐pot, three‐step, regioselective synthesis of 4‐substituted 1‐(2‐phenylselenocyclohexyl)‐1,2,3‐triazoles, involving in situ generation of l‐azido‐2‐phenylselenocyclohexane has been developed via four‐component reaction of phenylselenenyl bromide, cyclohexene, sodium azide and terminal alkynes catalyzed by copper iodide in a mixture of DMF/THF (1:1) at room temperature under mild conditions with simple workup and good yields. 相似文献
12.
Zhitong Zheng Huangfei Tu Prof. Dr. Liming Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(9):2445-2448
A two‐step, one‐pot synthesis of fused pyrroles is realized by firstly condensing an N‐alkynylhydroxammonium salt with a readily enolizable ketone under mild basic conditions and then subjecting the reaction mixture to a gold catalyst, which triggers a cascade reaction involving a facile initial [3.3]‐sigmatropic rearrangement of the gold‐catalysis product, that is, an N,O‐dialkenylhydroxamine. The reaction provides a facile access to polycyclic pyrroles in moderate to good yields. 相似文献
13.
Egor M. Larin Mark Lautens 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13572-13576
Acyl substituted triazoles are valuable scaffolds, but the direct synthesis of these moieties from terminal alkynes by copper catalysis remains unexplored. We report a robust, general, and efficient method using a simple CuI/2,2′‐bipyridine catalytic system. This transformation involves a copper catalyzed azide‐alkyne cycloaddition (CuAAC) followed by an intramolecular acylation onto a carbamoyl chloride. The reaction proceeds under mild conditions, tolerates several functional groups, and is readily scalable. This method represents a novel strategy towards the synthesis of complex heterocycles by a CuAAC/acylation domino process. 相似文献
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A convenient one‐pot synthesis of 2′‐amino‐ and 2′‐N‐phenylamino‐5α‐cholest‐6‐eno[6,7‐d]thiazole derivatives 4 ‐ 9 are reported. The synthesis involves the reaction of cholestan‐6‐ones 1 ‐ 3 with thiourea or phenylthiourea and iodine. The products have been characterized on the basis of IR, 1H‐NMR and Mass, which find support in two cases from comparison with authentic samples. 相似文献
17.
Zhenhua Liu Wenjing Hao Zhixian Liu Wen Gao Zhihai Zhang Yanan Zhang Xiang Li Lili Tong Bo Tang 《化学:亚洲杂志》2019,14(12):2149-2154
A bimetal‐catalyzed cascade reaction for the synthesis of N‐isopropenyl 1,2,3‐triazoles in high yield is reported. This reaction involves the generation of 2‐azidopropenes in situ by C(sp3)‐OAr bond cleavage for click reaction and features a broad substrate scope, good functional group tolerance and readily available substrates. 相似文献
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One‐Pot Cannizzaro Cascade Synthesis of ortho‐Fused Cycloocta‐2,5‐dien‐1‐ones from 2‐Bromo(hetero)aryl Aldehydes 下载免费PDF全文
Dr. Laurence Burroughs Lee Eccleshare John Ritchie Omkar Kulkarni Prof. Dr. Barry Lygo Prof. Dr. Simon Woodward Dr. William Lewis 《Angewandte Chemie (International ed. in English)》2015,54(36):10648-10651
An intramolecular Cannizzaro‐type hydride transfer to an in situ prepared allene enables the synthesis of ortho‐fused 4‐substituted cycloocta‐2,5‐dien‐1‐ones with unprecedented technical ease for an eight‐ring carboannulation. Various derivatives could be obtained from commercially available (hetero)aryl aldehydes, trimethylsilylacetylene, and simple propargyl chlorides in good yields. 相似文献