33491-02-0Relevant articles and documents
Transition-Metal-Free One-Step Synthesis of Ynamides
Zeng, Xianzhu,Tu, Yongliang,Zhang, Zhenming,You, Changming,Wu, Jiao,Ye, Zhiying,Zhao, Junfeng
, p. 4458 - 4466 (2019/03/26)
A robust transition-metal-free one-step strategy for the synthesis of ynamides from sulfonamides and (Z)-1,2-dichloroalkenes or alkynyl chlorides is presented. This method is not only effective for internal ynamides but also amenable for terminal ynamides. Various functional groups, even the vinyl moiety, are compatible, and thus, this strategy offers the opportunity for further functionalization.
Gold-Catalyzed Highly Chemo- and Regioselective C-H Bond Functionalization of Phenols with Haloalkynes
Adak, Tapas,Schulmeister, Jürgen,Dietl, Martin C.,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
supporting information, p. 3867 - 3876 (2019/06/25)
A highly chemo- and stereoselective addition of unprotected phenols to haloalkynes was developed. A ligand and counterion controlled process enabled the highly site-selective and chemoselective C-H bond functionalization of phenol derivatives with haloalkynes in moderate to excellent yield at room temperature. The simple availability of the starting materials in combination with the preferred para-C-H functionalization over a competing O-H insertion makes this an attractive protocol. The stereoselectivity of the products depends on the choice of the catalyst. From a synthetic prospective, this method offers an efficient route towards vinyl chlorides, which are valuable precursors for the synthesis of pharmaceutical drugs.
Highly efficient and recyclable catalyst for the direct chlorination, bromination and iodination of terminal alkynes
Shi, Wei,Guan, Zhipeng,Cai, Peng,Chen, Hao
, p. 199 - 204 (2017/08/10)
Direct halogenation, including chlorination, bromination and iodination of terminal alkynes, are of great importance in organic synthesis. Here an efficient and recyclable nano-Ag/g-C3N4 catalyst system was developed and proved to be remarkably active with 39 examples varied from chlorination, bromination to iodination, of which 14 runs have yielded more than 95% of the product. Recycling of the catalyst was also achieved without obvious activity loss after several runs: 99% yield was observed even after 5 runs in the bromination of phenylacetylene. The catalysts system is of low cost and easy to be prepared, making this procedure versatile, convenient and economic.
A copper (II) (II) composite chlorinating agent and copper-based composite chlorinating agent synthesis of 1-chloro-2-aryl acetylene method
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Paragraph 0028; 0102; 0106, (2016/11/24)
The invention discloses a copper (II) composite chlorinating agent and a method for synthesizing 1-chlorine-2-aryl acetylene based on the copper (II) composite chlorinating agent. The structural formula of the copper (II) composite chlorinating agent is CuCl2.xNaCl.yAl2O3. The chlorinating agent is applicable to chlorination of various substituted aryl acetylene substrates, and is high in universality; the chlorinating agent can directly carry out chlorination reaction on aryl acetylene so as to obtain a 1-chlorine-2-aryl acetylene product; the method is mild in reaction condition, 1-chlorine-2-aryl acetylene can be synthesized with high yield and high selectivity, and the production cost of the 1-chlorine-2-aryl acetylene derivative is greatly lowered.
Facile and efficient synthesis of 1-haloalkynes via DBU-mediated reaction of terminal alkynes and N-haloimides under mild conditions
Li, Mengru,Li, Yueju,Zhao, Baozhong,Liang, Fushun,Jin, Long-Yi
, p. 30046 - 30049 (2014/08/05)
Directly from terminal alkynes and with N-halosuccinimides (halo = Br and I) or N-cholorophthalimide as the halogen sources, DBU as the activator, 1-haloalkynes were prepared in good to excellent yields at room temperature. Bis(bromoalkyne) and bis(iodoal
Elusive ethynyl azides: Trapping by 1,3-dipolar cycloaddition and decomposition to cyanocarbenes
Banert, Klaus,Hagedorn, Manfred,Wutke, Jens,Ecorchard, Petra,Schaarschmidt, Dieter,Lang, Heinrich
supporting information; experimental part, p. 4058 - 4060 (2010/09/06)
Although they decompose rapidly to produce cyanocarbenes, ethynyl azides were generated from (chloroethynyl)arenes and trapped for the first time by 1,3-dipolar cycloaddition at cyclooctyne.
Analysis of substituent effects on C-13 NMR parameters of substituted arylacetylene derivatives. Linear free energy relationships and PM3 semiempirical calculations
Lin, Shaw-Tao,Lee, Chuan-Chen,Liang, David W.
, p. 9619 - 9623 (2007/10/03)
The substituent-induced chemical shifts (SCS) of C(α,β) on the 13C NMR spectra of arylalkynes (i.e. containing H, CH3, Cl and Br) were studied. The correlation between SCS and Hammett constants shows that the tendency of the effect by the substituents on the phenyl ring is Br (ρ=8.15)>Cl (ρ=7.27)>CH3 (ρ=6.79)>H (ρ=5.78). This order can be rationalized as due to the ability of the group on the alkyne to stabilize the partial positive charge on C(β) resulting from polarization with π electron transfer from C(β) to the phenyl ring. The SCS values are also well correlated with the electron densities obtained from PM3 calculations. The solvent effect on the 13C chemical shifts of phenylalkynyl bromide demonstrates a strong dependence on the relative permittivity as well as the shielding character of the solvents. (C) 2000 Elsevier Science Ltd.
PYROLYSIS OF α-HALOPHOSPHORANES -> HALOACETYLENES
Braga, Antoenio L.,Comasseto, Joaeo V.
, p. 2877 - 2884 (2007/10/02)
α-Halophosphoranes upon pyrolysis give haloacetylenes in moderate yields.
REACTION DE L'ACIDE PERCHLORIQUE SUR LES PHENYLACETYLENES SUBSTITUES. MISE EN EVIDENCE D'UN MECANISME IONIQUE ET RADICALAIRE
Montheard, Jean-Pierre,Camps, Marcel,Benzaid, Ahmed,Pascal, Jean-Louis
, p. 3483 - 3486 (2007/10/02)
We have studied the reaction of perchloric acid in acetic acid medium on some substituted phenylacetylenes.The ionic and radicalar mechanism is in agreement with the formation of and alkenyl perchlorate which is decomposed according to an homolytic process.
