共查询到20条相似文献,搜索用时 0 毫秒
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Woo‐Jin Yoo Thanh V. Q. Nguyen Sh Kobayashi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(38):10377-10381
A copper‐catalyzed multicomponent coupling reaction between in situ generated ortho‐arynes, terminal alkynes, and carbon dioxide was developed to access isocoumarins in moderate to good yields. The key to this CO2‐incorporating reaction was the use of a versatile N‐heterocyclic carbene/copper complex that was able to catalyze multiple transformations within the three‐component reaction. 相似文献
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Paige E. Piszel Aristidis Vasilopoulos Shannon S. Stahl 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(35):12339-12343
The aerobic Cu/ABNO catalyzed oxidative coupling of alcohols and amines is highlighted in the synthesis of amide bonds in diverse drug‐like molecules (ABNO=9‐azabicyclo[3.3.1]nonane N‐oxyl). The robust method leverages the privileged reactivity of alcohols bearing electronegative hetero‐ atoms (O, F, N, Cl) in the β‐position. The reaction tolerates over 20 unique functional groups and is demonstrated on a 15 mmol scale under air. Steric constraints of the catalyst allow for chemoselective amidation of primary amines in the presence of secondary amines. All catalyst components are commercially available, and the reaction proceeds under mild conditions with retention of stereocenters in both reaction partners, while producing only water as a by‐product. 相似文献
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Arunachalam Sagadevan V. Kishore Kumar Pampana Kuo Chu Hwang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(12):3878-3882
The first successful example of the three‐component coupling of N‐alkylanilines, terminal alkynes, and alcohols was achieved at room temperature by a visible‐light‐mediated copper‐catalyzed photoredox hydrogen‐atom transfer process. This method allows preparation of propargylamines through uniquely selective α‐C?H bond activation of unactivated alkylalcohols. Preliminary studies indicate that formation of α‐oxy radical is operative. This approach facilitates rapid access to biologically important propargylamines from methanol as an abundant feedstock. 相似文献
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Waqar Ahmed Sheng Zhang Xiaoqiang Yu Xiujuan Feng Yoshinori Yamamoto Ming Bao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2517-2521
The cooperative catalysis of copper, silver, and Brønsted acid is presented as a new strategy for olefin functionalization. The catalytic direct carbohydroxylation of arylalkenes with allylic alcohols provided a straightforward and efficient approach for preparing 4,5‐unsaturated alcohols. Synthetically useful functional groups, such as Cl, Br, carbonyl, and chloromethyl, remained intact during the functionalization reaction. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(33):10878-10882
The ability of mechanochemistry to alter established chemical selectivity is demonstrated. A copper(I)‐catalyzed mechanochemical aldehyde/alkyne/amine coupling using calcium carbide as the acetylene source provides selective access to 1,4‐diamino‐2‐butynes, which contrasts classical approaches that provide propargylamine‐type products. Solventless milling conditions were found to be essential to unmask A3 coupling products with new compositions. 相似文献
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Wenfang Xiong Chaorong Qi Haitao He Lu Ouyang Min Zhang Huanfeng Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(10):3127-3130
A base‐promoted three‐component coupling of carbon dioxide, amines, and N‐tosylhydrazones has been developed. The reaction is suggested to proceed via a carbocation intermediate and constitutes an efficient and versatile approach for the synthesis of a wide range of organic carbamates. The advantages of this method include the use of readily available substrates, excellent functional group tolerance, wide substrate scope, and a facile work‐up procedure. 相似文献
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Cemil İbiş F. Serpil Göksel Gökşin Aydınlı 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):777-783
Reaction of 2-nitropentachlorobutadiene with thiols and amines gave new N,S- and S,S-substituted nitrodiene compounds is discussed. 相似文献
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Devdutt CHATURVEDI Nisha MISHRA Virendra MISHRA 《中国化学快报》2006,17(10):1309-1312
Organic carbamates exhibit unique physical, chemical and biological properties, accommodating variety of applications in pharmacology1 (drugs, prodrugs and drug intermediates), agriculture2 (pesticides, insecticides, fungicides, herbicides etc.) and as synthetic intermediates in chemical industry3. Their use as protection of amino groups in peptide synthesis4 and as linkers in combinatorial chemistry5 is also well known. Functionalization of amines as carbamates offers an attractive method for… 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(36):10936-10940
Unified, efficient, and scalable syntheses of the halichondrin natural products are reported. A newly developed Zr/Ni‐mediated one‐pot ketone synthesis was used to couple the two halves of the final product at a late stage in the synthesis. With the use of a slight excess of the left halves, the desired ketones were isolated in yields of 80–90 %. The halichondrins were obtained from these ketones in two steps, namely desilylation and [5,5]‐spiroketal formation. The new synthetic route was effective for the total synthesis of all members in the homohalichondrin subgroup. The scalability of this process was demonstrated with halichondrin B; 150 mg of halichondrin B (68 % overall yield) were obtained from 200 mg of the right‐half precursor. 相似文献
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Selenium and copper synergistically catalyzed the oxidation/alkoxylation of methyl ketones to synthesize α‐keto acetals directly. Using O2 as oxidant and alcohol as solvent and alkoxylation reagent, the reaction is practical from industrial viewpoint. Mechanistic studies revealed that copper promoted the oxidation of organoselenium intermediates with O2 to allow the key rearrangement and selenoxide syn‐elimination regenerating the catalytically active organoselenium species. 相似文献
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Hamideh Ahankar Ali Ramazani Yavar Ahmadi Issa Amini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):886-894
Abstract Reactions of N-isocyaniminotriphenylphosphorane (Ph3PNNC) with aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) in the presence of 3-phenyl-2-propynoic acid and secondary amines proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed. 相似文献