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1.
A facile and practical synthetic route of unsymmetrical 1,3‐diynes via the PdCl/CuI catalyzed oxidative coupling of two different terminal alkynes has been developed by using 3‐(diphenylphosphino)propanoic acid as a ligand in the presence of oxygen. This system is suitable for not only aromatic alkynes but also heteroaromatic and aliphatic alkynes which were transformed into the corresponding unsymmetrical 1,3‐diynes in moderate to good yields at room temperature. Moreover, the unsymmetrical 1,3‐diynes were also obtained on a multi‐gram scale. Mechanistic studies suggest that oxygen plays a key role in the catalytic cycles. 相似文献
2.
A facile and direct fluorination process of alkynes and diynes was developed. In the presence of n‐butyllithium, the reaction of a series of terminal alkynes and diynes with the electrophilic fluorinating reagent (NFSI) proceeded to afford various 1‐fluoroalkynes and 1‐fluoro‐1,3‐diynes in moderate to high yields. 相似文献
3.
Formal [4+2] Reaction between 1,3‐Diynes and Pyrroles: Gold(I)‐Catalyzed Indole Synthesis by Double Hydroarylation
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Yuka Matsuda Saori Naoe Dr. Shinya Oishi Prof. Dr. Nobutaka Fujii Prof. Dr. Hiroaki Ohno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1463-1467
Indole synthesis by a gold(I)‐catalyzed intermolecular formal [4+2] reaction between 1,3‐diynes and pyrroles has been developed. This reaction involves the hydroarylation of 1,3‐diynes with pyrroles followed by an intramolecular hydroarylation to give the 4,7‐disubstituted indoles. This reaction can also be applied to the synthesis of carbazoles when indoles are used as the nucleophiles instead of pyrroles. 相似文献
4.
A simple and efficient protocol for CuI‐catalyzed oxidative homocoupling reaction of terminal alkynes to symmetrical 1,4‐disubstituted 1,3‐diynes was reported. The reaction can be carried out in the open air, using NaOAc as a base in the absence of any other additives. A variety of terminal alkynes were converted to the corresponding 1.3‐diynes in good to excellent yields without any side product formation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
5.
Zhishuo Wang Jiangliang Yin Fulin Zhou Yunqi Liu Jingsong You 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):260-264
Reported herein is a rhodium(III)‐catalyzed three‐component annulation reaction of simple pyridines, alkynes, and 1,2‐dichloroethane (DCE), affording a streamlined pathway to diverse ring‐fused pyridiniums. DCE not only serves as a vinyl equivalent but also as an in situ activating agent for pyridine C2?H activation. A cationic five‐membered rhodacycle complex has been isolated and proposed as a possible intermediate. This strategy can be extended to other N‐containing heteroarenes for the synthesis of multiring‐fused pyridiniums. These multicomponent reactions exhibit excellent regioselectivity for 1,3‐diynes, paving a path to the cascade cyclization of 3‐fluoropyridine or N‐methylpyridin‐3‐amine with 1,3‐diynes for the construction of brand‐new tricyclic‐fused pyrano‐ or hydropyridoquinolizinium salts. These ionic fluorophores have been investigated as potential biomarkers. 相似文献
6.
Highly Efficient Cycloaddition Reaction of 1,3‐Diynes with Sodium Azide: A New Way to 5‐Substituted‐4‐acetylene‐1H‐1,2,3‐triazoles
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A cycloaddition reaction of a range of 1,3‐diynes with sodium azide has been realized, which provided 5‐substituted‐4‐acetylene‐1H‐1,2,3‐triazoles in 75–99% yields. The chemical structures of the new compounds 3 are established by IR, NMR, Mass, and HRMS. 相似文献
7.
Prof. Dr. Yoshihiko Yamamoto Shota Mori Dr. Masatoshi Shibuya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(36):12034-12041
The transfer‐hydrogenative cyclization of 1,6‐diynes with Hantzsch 1,4‐dihydropyridine as a H2 surrogate was performed in the presence of a cationic ruthenium catalyst of the type [Cp′Ru(MeCN)3PF6]. Exocyclic 1,3‐dienes or their 1,4‐hydrogenation products, cycloalkenes, were selectively obtained, depending on the substrate structure and the reaction conditions. 相似文献
8.
Jiawang Liu Ji Yang Wolfgang Baumann Ralf Jackstell Matthias Beller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10793-10797
The stereoselective synthesis of conjugated dienes was realized for the first time via Pd‐catalyzed alkoxycarbonylation of easily available 1,3‐diynes. Key to success is the utilization of the specific ligand 1,1′‐ferrocenediyl‐bis(tert‐butyl(pyridin‐2‐yl)phosphine) ( L1 ), which allows this novel transformation to proceed at room temperature. A range of 1,2,3,4‐tetrasubstituted conjugated dienes are obtained in this straightforward access in high yields and selectivities. The synthetic utility of the protocol is showcased in the concise synthesis of several important intermediates for construction of natural products rac‐cagayanin, rac‐galbulin, rac‐agastinol, and cannabisin G. 相似文献
9.
The CH Activation/1,3‐Diyne Strategy: Highly Selective Direct Synthesis of Diverse Bisheterocycles by RhIII Catalysis
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Dr. Da‐Gang Yu Francisco de Azambuja Tobias Gensch Dr. Constantin G. Daniliuc Prof. Dr. Frank Glorius 《Angewandte Chemie (International ed. in English)》2014,53(36):9650-9654
The reactivity and selectivity of 1,3‐diynes in transition‐metal‐catalyzed C? H activation is exploited to quickly assemble diverse polysubstituted bisheterocycles, which are highly important but difficult to access. By using the C? H activation/1,3‐diyne strategy, we overcame the challenges of selectivity (chemo‐, regio‐, and mono‐/diannulation) and constructed seven kinds of adjacent bisheterocycles through the formation of four strategic bonds with high efficiency and high selectivity. 相似文献
10.
Two NHC–Pd(II) complexes synthesized from trans‐cyclohexane‐1,2‐diamine were fairly effective in the NHC–Pd(II) complex/Cu co‐catalyzed terminal alkyne homocoupling reaction to give the corresponding symmetrical 1,4‐disubstituted 1,3‐diynes in good yields under mild conditions. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
11.
Jiawang Liu Ji Yang Carolin Schneider Robert Franke Ralf Jackstell Matthias Beller 《Angewandte Chemie (International ed. in English)》2020,59(23):9032-9040
For the first time, the monoalkoxycarbonylation of easily available 1,3‐diynes to give synthetically useful conjugated enynes has been realized. Key to success was the design and utilization of the new ligand 2,2′‐bis(tert‐butyl(pyridin‐2‐yl)phosphanyl)‐1,1′‐binaphthalene (Neolephos), which permits the palladium‐catalyzed selective carbonylation under mild conditions, providing a general preparation of functionalized 1,3‐enynes in good‐to‐high yields with excellent chemoselectivities. Synthetic applications that showcase the possibilities of this novel methodology include an efficient one‐pot synthesis of 4‐aryl‐4H‐pyrans as well as the rapid construction of various heterocyclic, bicyclic, and polycyclic compounds. 相似文献
12.
CuCl with the use of a catalytic amount of piperidine as additive shows high catalytic activity for the oxidative homocoupling reactions of terminal alkynes in toluene at 60 °C in air to afford 1,3‐diynes in high yields. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
13.
First report of a nano‐Cu2O‐catalyzed protocol for homo‐coupling reaction of terminal alkynes in water/ionic liquid medium
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Bo‐Xiao Tang Xiao‐Niu Fang Ren‐Yun Kuang Jian‐Hong Wu Qiao Chen Shao‐Jun Hu Yi‐Lin Liu 《应用有机金属化学》2016,30(11):943-945
A new, efficient and green protocol for the nano‐Cu2O‐catalyzed homo‐coupling reaction of terminal alkynes has been developed, using water/ionic liquid as an environmentally friendly solvent. Moreover, the system also allows the synthesis of unsymmetric 1,3‐diynes by cross‐coupling of two different terminal alkynes. It is noteworthy that the nano‐Cu2O‐catalyzed methodology is a good supplement to copper catalyst for the Glaser‐type homo‐coupling reaction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
14.
Yoshihiko Yamamoto Prof. Dr. Ken Yamashita Tomitaka Hotta Toru Hashimoto Makoto Kikuchi Dr. Hisao Nishiyama Prof. Dr. 《化学:亚洲杂志》2007,2(11):1388-1399
Spirocyclic C‐arylglycosides were synthesized from the appropriately protected δ‐gluconolactones. Addition of lithium acetylide followed by glycosylation with 3‐(trimethylsilyl)propargyl alcohol converted the δ‐gluconolactones into silylated diynes. After desilylation, subsequent ruthenium‐catalyzed cycloaddition of the resultant diynes with alkynes or chloroacetonitrile gave spirocyclic C‐arylglycosides in good yields and selectivity. This strategy was also extended to the synthesis of spirocyclic C‐arylribosides from the known γ‐ribonolactone derivative. Moreover, silver‐catalyzed iodination of the sugar diynes followed by ruthenium‐catalyzed cycloaddition with acetylene delivered spirocyclic C‐iodophenylglycosides and ‐ribosides, which were subjected to palladium‐catalyzed C? C bond‐forming reactions and copper‐catalyzed coupling with nitrogen heterocycles to lead to various derivatives. 相似文献
15.
Copper‐Catalyzed Aerobic Oxidative Transformation of Ketone‐Derived N‐Tosyl Hydrazones: An Entry to Alkynes
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Xianwei Li Xiaohang Liu Huoji Chen Dr. Wanqing Wu Dr. Chaorong Qi Prof. Dr. Huanfeng Jiang 《Angewandte Chemie (International ed. in English)》2014,53(52):14485-14489
A novel strategy involving Cu‐catalyzed oxidative transformation of ketone‐derived hydrazone moiety to various synthetic valuable internal alkynes and diynes has been developed. This method features inexpensive metal catalyst, green oxidant, good functional group tolerance, high regioselectivity and readily available starting materials. Oxidative deprotonation reactions were carried out to form internal alkynes and symmetrical diynes. Cross‐coupling reactions of hydrazones with halides and terminal alkynes were performed to afford functionalized alkynes and unsymmetrical conjugated diynes. A mechanism proceeding through a Cu‐carbene intermediate is proposed for the C? C triple bond formation. 相似文献
16.
《应用有机金属化学》2017,31(12)
The application of non‐toxic and magnetically separable nano‐CuFe2O4 as an efficient catalyst for oxidative homo‐ and cross‐coupling reaction of terminal alkynes is described. A wide range of symmetrical and unsymmetrical 1,3‐diynes have been synthesized in moderate to good yields under ambient atmosphere. The nano CuFe2O4 can be recovered with a magnet and reused at least five consecutive cycles with no appreciable loss of its catalytic activity. 相似文献
17.
3‐(Diphenylphosphino)propanoic acid: an efficient ligand for the Pd/Cu‐catalyzed homo‐coupling of terminal alkynes in the presence of oxygen at room temperature
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Yashuai Liu Ningning Gu Ping Liu Jianwei Xie Xiaowei Ma Yan Liu Bin Dai 《应用有机金属化学》2015,29(11):736-738
A simple, yet efficient system for PdCl2/CuI to catalyze the homo‐coupling reactions of various terminal alkynes has been developed using 3‐(diphenylphosphino)propanoic acid as ligand in the presence of oxygen. The alkynes, including aromatic, heteroaromatic and aliphatic alkynes, were transformed at room temperature into the corresponding 1,3‐diynes in moderate to excellent yields. The turnover number was up to 1.04 × 103. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
18.
Insights into the Gold‐Catalyzed Propargyl Ester Rearrangement/Tandem Cyclization Sequence: Radical versus Gold Catalysis—Myers–Saito‐ versus Schmittel‐Type Cyclization
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Dipl.‐Chem. Eva Rettenmeier Dr. Max M. Hansmann Alexander Ahrens Katharina Rübenacker Tapish Saboo Joy Massholder Christian Meier Dr. Matthias Rudolph Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14401-14409
A detailed study of the gold‐catalyzed tandem 1,3‐carboxy migration/allene–enyne cycloisomerization was undertaken. It was found that after the initial allene formation the selectivity of the reaction is strongly influenced by the polarization of the remaining alkyne. Depending on the substitution pattern of the starting diynes, either a Schmittel‐ or a Myers–Saito‐type cyclization was triggered. The 6‐endo‐dig Myers–Saito‐type cyclization gave access to benzo[b]fluorenes, while the Schmittel pathway (5‐exo‐dig) delivered benzofulvenes as final products. In special cases a yet unknown pathway was opened by the ambiphilic nature of the allene moiety. In these cases completely different products were obtained by the nucleophilic attack of the alkyne moiety onto the allene that can also act as an electrophile. Mechanistic studies revealed that diradical pathways can be ruled out for this type of tandem cyclization reactions and it is shown that both steps of the reaction cascade are catalyzed by the gold complex. 相似文献
19.
A simple and efficient protocol for Fe/Cu cocatalyzed oxidative homocoupling reaction of terminal alkynes to symmetrical 1,4‐disubstituted‐1,3‐diynes was presented. The results showed that both CuBr and FeCl3 played crucial roles in the reaction. It is noteworthy that this protocol employs mild, efficient, aerobic and ligand free conditions. The alkynes, including aromatic, heteroaromatic and aliphatic alkynes, were transformed into the corresponding 1,3‐diynes in good to excellent yields. 相似文献
20.
Catalytic Enantioselective Conjugate Alkynylation of α,β‐Unsaturated 1,1,1‐Trifluoromethyl Ketones with Terminal Alkynes
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Dr. Amparo Sanz‐Marco Prof. Dr. Gonzalo Blay Prof. Dr. M. Carmen Muñoz Prof. Dr. José R. Pedro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10057-10064
The first catalytic enantioselective conjugate alkynylation of α,β‐unsaturated 1,1,1‐trifluoromethyl ketones has been carried out. Terminal alkynes and 1,3‐diynes were treated with trifluoromethyl ketones in the presence of a low catalytic load of a CuI‐MeOBIPHEP complex (2.5 mol %) and triethylamine (10 mol %) to give the corresponding trifluoromethyl ketones bearing a propargylic stereogenic center at the β position with good yields and excellent enantiomeric excesses in most of the cases. No 1,2‐addition products were formed under the reaction conditions. The procedure showed broad substrate scope for alkyne, diyne, and enone. A rationale for the observed stereochemistry has been provided. Finally, the potential application of the reaction products in the synthesis of chiral tetrahydrofurans bearing a trifluoromethylated quaternary stereocenter has been devised. 相似文献