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1.
Oxidative acylation of α,α‐diarylallylic alcohols: Synthesis of 1,2,4‐triarylbutane‐1,4‐diones
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Yong Li Yuting Leng Shiwei Wang Yuhui Gao Huiyan Lv Junbiao Chang Yusheng Wu Yangjie Wu 《应用有机金属化学》2018,32(8)
A metal‐free mediated oxidative acylation of α,α‐diarylallylic alcohols with simple aromatic aldehydes for the synthesis of 1,2,4‐triphenylbutane‐1,4‐diones is presented. In the presence of TBPB (tert‐butyl peroxybenzoate), desired products were obtained in good to excellent yields for 28 examples. This protocol features high regioselectivity, wide functional group tolerance and atom economy. 相似文献
2.
An atom economic and facile synthesis of novel dispiro–oxindole–pyrrolidines has been achieved via a three‐component tandem cycloaddition of azomethine ylide generated in situ from isatin and sarcosine by decarboxylative condensation with N‐aryl‐3‐benzylidene‐pyrrolidine‐2,5‐dione derivatives as dipolarophiles. The salient features of synthetic procedure are characterized by the mild reaction conditions, high yields, high regioselectivity and stereoselectivity, one‐pot procedure, and operational simplicity. This regioselectivity was assumed to be under the influence of π–π stacking interactions between the aromatic rings of azomethine ylide and N‐aryl‐3‐benzylidene‐pyrrolidine‐2,5‐diones that further control the exo–endo selectivity of the reaction 1,3‐dipolar cycloaddition. The regiochemistry and structures of the cycloadducts were determined with spectroscopic data. 相似文献
3.
An Organocatalytic Azide–Aldehyde [3+2] Cycloaddition: High‐Yielding Regioselective Synthesis of 1,4‐Disubstituted 1,2,3‐Triazoles
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Prof. Dr. Dhevalapally B. Ramachary Adluri B. Shashank S. Karthik 《Angewandte Chemie (International ed. in English)》2014,53(39):10420-10424
An organocatalytic azide–aldehyde [3+2] cycloaddition (organo‐click) reaction of a variety of enolizable aldehydes is reported. The organo‐click reaction is characterized by a high rate and regioselectivity, mild reaction conditions, easily available substrates with simple operation, and excellent yields with a broad spectrum of substrates. It constitutes an alternative to the previously known CuAAC, RuAAC, and IrAAC click reactions. 相似文献
4.
The reaction of prop‐1‐ene‐1,3‐sultone 1 with a variety of nitrile oxides 3 afforded novel [3+2] cycloaddition products 4 in good yield. The cycloaddition reaction achieved excellent regioselectivity. 相似文献
5.
Highly Selective Construction of Seven‐Membered Carbocycles by Olefin‐Assisted Palladium‐Catalyzed Oxidative Carbocyclization–Alkoxycarbonylation of Bisallenes
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Dr. Can Zhu Bin Yang Dr. Youai Qiu Prof. Dr. Jan‐E. Bäckvall 《Angewandte Chemie (International ed. in English)》2016,55(46):14405-14408
An olefin‐assisted palladium‐catalyzed oxidative carbocyclization–alkoxycarbonylation of bisallenes to afford seven‐membered carbocycles has been established. This dehydrogenative coupling reaction showed excellent substrate scope and functional group compatibility. The reaction exhibited high chemo‐ and regioselectivity, and ester 3 was the only product obtained. The olefin unit has been proven to be indispensable during the reaction. Moreover, intramolecular oxidative coupling suggests that the reaction proceeds via a (π‐allyl)palladium intermediate. 相似文献
6.
《中国化学》2017,35(11):1717-1725
A facile and efficient route to 4‐aryl‐2‐[2‐(trifluoromethylthio) aryl]quinazoline derivatives through a tandem directed Rh‐catalyzed C‐H iodination and trifluoromethylthiolation is described. The reaction proceeded under mild reaction conditions, exhibited good functional group tolerance with a broad scope of substrate and excellent regioselectivity in good to excellent yields. 相似文献
7.
Regio‐ and Enantioselective Aza‐Diels–Alder Reactions of 3‐Vinylindoles: A Concise Synthesis of the Antimalarial Spiroindolone NITD609
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Haifeng Zheng Prof. Dr. Xiaohua Liu Chaoran Xu Yong Xia Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2015,54(37):10958-10962
An asymmetric aza‐Diels–Alder reaction of 3‐vinylindoles with isatin‐derived ketimines has been developed. A series of spiroindolone derivatives were thus obtained in good to excellent yields with excellent enantioselectivity (up to 96 % yield and 99 % ee). Furthermore, the antimalarial compound NITD609 could be obtained in three steps with an overall yield of 40.6 %. Control experiments and operando IR experiments imply a concerted reaction pathway. The regioselectivity and exo selectivity result from π–π interactions between the two indoline rings of the two reactants. 相似文献
8.
Herein, we report a practical protocol for the synthesis of sulfur cycle fused 1,2,3‐triazoles through a copper(I)‐catalyzed tandem click/intramolecular sulfenylation reaction. The reaction proceeded via a copper‐catalyzed alkyne azide cycloaddition, followed by interception of the in situ formed cuprate‐triazole intermediate with p‐toluenesulfonothioate. This reaction shows broad substrate scope, complete regioselectivity, and excellent functional group tolerance under mild reaction conditions. 相似文献
9.
Asymmetric Synthesis of Hydrocarbazoles Catalyzed by an Octahedral Chiral‐at‐Rhodium Lewis Acid
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A bis‐cyclometalated chiral‐at‐metal rhodium complex catalyzes the Diels–Alder reaction between N‐Boc‐protected 3‐vinylindoles (Boc=tert‐butyloxycarbonyl) and β‐carboxylic ester‐substituted α,β‐unsaturated 2‐acyl imidazoles with good‐to‐excellent regioselectivity (up to 99:1) and excellent diastereoselectivity (>50:1 d.r.) as well as enantioselectivity (92–99 % ee) under optimized conditions. The rhodium catalyst serves as a chiral Lewis acid to activate the 2‐acyl imidazole dienophile by two‐point binding and overrules the preferred regioselectivity of the uncatalyzed reaction. 相似文献
10.
Catalytic Asymmetric Synthesis of [2,3]‐Fused Indoline Heterocycles through Inverse‐Electron‐Demand Aza‐Diels–Alder Reaction of Indoles with Azoalkenes
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Min‐Chao Tong Xuan Chen Jun Li Rong Huang Haiyan Tao Prof. Dr. Chun‐Jiang Wang 《Angewandte Chemie (International ed. in English)》2014,53(18):4680-4684
An unprecedented catalytic asymmetric inverse‐electron‐demand aza‐Diels–Alder reaction of indoles with in situ formed azoalkenes is reported. A diverse set of [2,3]‐fused indoline heterocycles were achieved in generally good yields (up to 97 %) with high regioselectivity and diastereoselectivity (>20:1 d.r.), and with excellent enantioselectivity (up to 99 % ee). 相似文献
11.
Dr. Hayato Ishikawa Takaki Suzuki Dr. Hideo Orita Dr. Tadafumi Uchimaru Prof. Dr. Yujiro Hayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(42):12616-12626
The efficient asymmetric total synthesis of (?)‐oseltamivir, an antiviral reagent, has been accomplished by using two “one‐pot” reaction sequences, with excellent overall yield (60 %) and only one required purification by column chromatography. The first one‐pot reaction sequence consists of a diphenylprolinol silyl ether mediated asymmetric Michael reaction, a domino Michael reaction/Horner–Wadsworth–Emmons reaction combined with retro‐aldol/Horner–Wadsworth–Emmons reaction and retro Michael reactions, a thiol Michael reaction, and a base‐catalyzed isomerization. Six reactions can be successfully conducted in the second one‐pot reaction sequence; these are deprotection of a tert‐butyl ester and its conversion into an acyl chloride then an acyl azide, Curtius rearrangement, amide formation, reduction of a nitro group into an amine, and a retro Michael reaction of a thiol moiety. A column‐free synthesis of (?)‐oseltamivir has also been established. 相似文献
12.
An Elegant Synthesis of a New Class of 1‐(Substituted)‐1H‐1,2,3‐triazol‐4‐yl)methyl)diphenylphosphineoxides by Microwave Irradiation
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Radha Rani Chinthaparthi Chandra Sekhar Reddy Gangireddy Madhu Kumar Reddy Kandula Satheesh Krishna Balam Suresh Reddy Cirandur 《Journal of heterocyclic chemistry》2015,52(6):1876-1882
A simple and efficient one‐pot microwave‐assisted click formation of 1‐(substituted)‐1H‐1,2,3‐triazol‐4‐yl)methyl)diphenylphosphineoxide derivatives via Huisgen regioselective [3+2]‐cycloaddition of an in situ generated organic azides and diphenyl(prop‐2‐yn‐1‐yl)phosphine oxide in highly polar DMSO‐H2O medium. This synthetic protocol is mild, requires shorter reaction time, and afforded products in excellent yields with high regioselectivity. 相似文献
13.
Firouz Matloubi Moghaddam Mostafa Kiamehr Mohammad Reza Khodabakhshi Marjan Jebeli Javan Shaghayegh Fathi Alexander Villinger Viktor O. Iaroshenko Peter Langer 《Helvetica chimica acta》2013,96(11):2103-2114
An efficient one‐pot, three‐component synthesis of novel dispiro[oxindole‐3,3′‐pyrrolidines] by 1,3‐dipolar cycloaddition of azomethine ylides, in situ generated by reaction of 1,2‐diones with sarcosine and subsequent decarboxylation, with a series of (E)‐3‐benzylidene‐2,3‐dihydro‐1H‐indol‐2‐ones is reported. Molecular complexity is generated in only one synthetic step. All reactions proceed with excellent regioselectivity and in good‐to‐excellent yields. The workup is easy, the reaction times are short, and no catalyst is required. 相似文献
14.
Clay‐supported copper(II) nitrate (claycop) has been used as an efficient catalyst for azide–alkyne cycloaddition reactions leading to 1,4‐disubstituted 1,2,3‐triazoles. The highly efficient claycop/hydrazine hydrate catalytic system affords triazoles in a few minutes (1–20 min) at room temperature, under mild and solvent‐free conditions. High regioselectivity, excellent yields, ease of claycop synthesis and recyclability/reusability of the catalyst are considered as practical merits of the protocol. 相似文献
15.
An efficient proline‐catalyzed synthesis of 4,5‐disubstituted‐N‐sulfonyl‐1,2,3‐triazoles has been accomplished from 1,3‐dicarbonyl compounds and sulfonyl azides. The developed reaction is suitable for various symmetrical and unsymmetrical 1,3‐dicarbonyl compounds, tolerates various functional groups and affords 4,5‐disubstituted‐N‐sulfonyl‐1,2,3‐triazoles in good yield with excellent regioselectivity. Rhodium‐catalyzed denitrogenative functionalization of 4,5‐disubstituted‐N‐sulfonyl‐1,2,3‐triazoles further demonstrates their utility in organic synthesis. 相似文献
16.
Enantioselective Formal [3+3] Cycloadditions of Ketones and Cyclic 1‐Azadienes by Cascade Enamine–Enamine Catalysis
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Xiao‐Long He You‐Cai Xiao Wei Du Prof.Dr. Ying‐Chun Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3443-3448
An asymmetric formal [3+3] cycloaddition process with diversely structured aliphatic ketones and electron‐deficient cyclic 1‐azadienes was developed by cascade enamine–enamine catalysis of a cinchona‐based primary amine. This sequence involved a domino Michael addition–Mannich reaction to afford spirocyclic architectures in excellent diastereo‐ and enantioselectivity. Importantly, high regioselectivity was realized for a number of unsymmetrical aliphatic ketone substrates. 相似文献
17.
This work reported a convenient method for the preparation of enantiomerically pure 6‐aryl‐2,2′‐dihydroxy‐1,1′‐binaphthyl derivatives starting from the commercially available (R)‐2,2′‐hydroxy‐1,1′‐binaphthyl [(R)‐ 1 ] via bromination, hydrolysis and Suzuki cross coupling reaction. This novel synthetic method was characterized with high regioselectivity, simple operation, mild reaction conditions, and excellent yield (up to 73%). On the other hand, we synthesized the target unknown compounds, which were confirmed by IR, 1H NMR, 13C NMR, MS and elementary analysis. 相似文献
18.
Bao‐Le Li Wei‐Yang Gao Han Li Shuo‐Qing Zhang Xiao‐Qing Han Jun Lu Ren‐Xiao Liang Xin Hong Yi‐Xia Jia 《中国化学》2019,37(1):63-70
An enantioselective desymmetric nucleophilic α‐addition of cyclohexanone to propiolamide has been developed through a 6‐exo‐dig cyclization reaction. By employing simple and readily available L‐proline sodium salt as a bifunctional catalyst, a series of chiral 6,6‐bicyclic bridged products bearing morphan scaffold have been isolated in good yields and excellent enantioselectivities. Density functional theory (DFT) calculations elucidated the origins of the enantioselectivity and regioselectivity of this transformation. A salt bridge that links the amide carbonyl group with proline carboxylate in the transition state was proven to be the driving force for the induction of excellent enantioselectivity. 相似文献
19.
Facial Synthesis of o‐Carborane‐Substituted Alkenes and Allenes by a Regioselective Ene Reaction of 1,3‐Dehydro‐o‐carborane
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Da Zhao Jiji Zhang Prof.Dr. Zuowei Xie 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(29):10334-10337
1,3‐Dehydro‐o‐carborane is a useful synthon for selective cage boron functionalization of o‐carboranes. It reacts readily with alkenes or alkynes to give a variety of cage B(3)‐alkenyl/allenyl o‐carboranes by ene reactions in very high yields and excellent regioselectivity. This can be ascribed to the highly polarized cage C?B multiple bond, which lowers the activation barriers of the ene reaction. 相似文献
20.
Divergent Synthesis of CF3‐Substituted Allenyl Nitriles by Ligand‐Controlled Radical 1,2‐ and 1,4‐Addition to 1,3‐Enynes
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Fei Wang Dinghai Wang Yu Zhou Ling Liang Ronghua Lu Dr. Pinhong Chen Prof. Dr. Zhenyang Lin Prof. Dr. Guosheng Liu 《Angewandte Chemie (International ed. in English)》2018,57(24):7140-7145
A ligand‐controlled system that enables regioselective trifluoromethylcyanation of 1,3‐enynes has been identified, which provides access to a variety of CF3‐containing tri‐ and tetrasubstituted allenyl nitriles. We disclose that the involved propargylic radicals can be selectively trapped by (Box)CuII cyanide, while the tautomerized allenyl radicals are trapped by (phen)CuII cyanide (Box= bisoxazoline, phen=phenanthroline). In addition, the reaction features broad substrate scope and excellent functional group compatibility. Moreover, this protocol represents a novel regioselectivity‐tunable functionalization of 1,3‐enynes via radicals, which we believe will have great implications for the development of catalytic systems for selectivity control in radical and organometallic chemistry. 相似文献