33491-04-2Relevant articles and documents
Method for preparing 1-halogenated alkyne under catalysis of heterogeneous Ag catalyst at room temperature
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Paragraph 0023-0036; 0040, (2021/05/12)
The invention discloses a novel method for preparing 1-halogenated alkyne under the catalysis of a heterogeneous Ag catalyst at room temperature. The method comprises the steps of mixing terminal alkyne compounds containing different substituent groups, N
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.
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.
Au-Catalyzed Intermolecular [2+2] Cycloadditions between Chloroalkynes and Unactivated Alkenes
Bai, Yu-Bin,Luo, Zaigang,Wang, Yuguang,Gao, Jin-Ming,Zhang, Liming
, p. 5860 - 5865 (2018/05/14)
The [2+2] cycloaddition is a versatile strategy for the synthesis of strained cyclobutenes of high synthetic value. In this study, two efficient intermolecular [2+2] cycloadditions between two different types of chloroalkynes and unactivated alkene are realized with gold catalysis. Of significance is that the reaction works with challenging monosubstituted unactivated alkenes, which is unprecedented in gold catalysis and scarcely documented in other metal-catalyzed/promoted reactions; moreover, the reaction exhibits excellent regioselectivities, which are much better than those reported in literature. With 1,2-disubstituted unactivated alkenes, the reaction is largely stereospecific. The cyclobutene products can be prepared in nearly gram scale and readily undergo further reactions including various cross-coupling reactions using the C(sp2)-Cl and/or C(sp2)-SPh bond, which in turn substantially broaden the scope of accessible cyclobutenes and enhance the synthetic utility of this bimolecular reaction.
Sequential Functionalization of Alkynes and Alkenes Catalyzed by Gold(I) and Palladium(II) N-Heterocyclic Carbene Complexes
Gómez-Herrera, Alberto,Nahra, Fady,Brill, Marcel,Nolan, Steven P.,Cazin, Catherine S. J.
, p. 3381 - 3388 (2016/11/16)
The iodination of terminal alkynes for the synthesis of 1-iodoalkynes using N-iodosuccinimide in the presence of a AuI-NHC (NHC=N-heterocyclic carbene) catalyst is reported. A series of aromatic alkynes was transformed successfully into the corresponding 1-iodoalkynes in good to excellent yields under mild reaction conditions. The further use of these compounds as organic building blocks and the advantageous choice of metal-NHC complexes as catalysts for alkyne functionalization were further demonstrated by performing selective AuI-catalyzed hydrofluorination to yield (Z)-2-fluoro-1-iodoalkenes, followed by a Suzuki–Miyaura cross-coupling with aryl boronic acids catalyzed by a PdII-NHC complex to access trisubstituted (Z)-fluoroalkenes. All methodologies can be performed sequentially with only minor variations in the optimized individual reaction conditions, maintaining high efficiency and selectivity in all cases, which therefore, provides straightforward access to valuable fluorinated alkenes from commercially available terminal alkynes.
Silver-catalyzed synthesis of 1-chloroalkynes directly from terminal alkynes
Shi, Dunfa,Liu, Zhiwen,Zhang, Ziyu,Shi, Wei,Chen, Hao
, p. 1424 - 1426 (2015/06/10)
An efficient method to prepare 1-chloroalkynes was investigated. The method involved the use of readily available terminal alkynes and a catalytic amount of a silver salt with N-chlorosuccinimide as the chlorinating agent under mild conditions. Compared with the existing process, this method has a broad substrate scope: 19 examples were explored, and the products were obtained in excellent yields and were easily isolated by vacuum distillation. Moreover, recycling of the catalyst was achieved by simple filtration and desiccation, which made the method more economic and environmentally benign.
An improved transition-metal-free synthesis of aryl alkynyl sulfides via substitution of a halide at an sp-centre
Chowdhury, Roomi Mohima,Wilden, Jonathan D.
supporting information, p. 5859 - 5861 (2015/06/02)
A simple high-yielding preparation of aryl alkynyl sulfides is presented. The reaction of a chloroacetylene with a thiolate salt in the presence of an amine mediator (dimethylamine or N,N′-dimethylethylenediamine) yields the alkynyl sulfides in excellent yields. The alkynyl chloride is easily prepared from the parent alkyne.
Regioselective Synthesis of Polyheterohalogenated Naphthalenes via the Benzannulation of Haloalkynes
Lehnherr, Dan,Alzola, Joaquin M.,Lobkovsky, Emil B.,Dichtel, William R.
supporting information, p. 18122 - 18127 (2015/12/24)
Independent control of halide substitution at six of the seven naphthalene positions of 2-arylnaphthalenes is achieved through the regioselective benzannulation of chloro-, bromo-, and iodoalkynes. The modularity of this approach is demonstrated through the preparation of 44 polyheterohalogenated naphthalene products, most of which are difficult to access through known naphthalene syntheses. The outstanding regioselectivity of the reaction is both predictable and proven unambiguously by single-crystal X-ray diffraction for many examples. This synthetic method enables the rapid preparation of complex aromatic systems poised for further derivatization using established cross-coupling methods. The power and versatility of this approach makes substituted naphthalenes highly attractive building blocks for new organic materials and diversity-oriented synthesis.
A versatile and highly efficient method for 1-chlorination of terminal and trialkylsilyl-protected alkynes
Gulia, Nurbey,Pigulski, Bartlomiej,Charewicz, Marta,Szafert, Slawomir
supporting information, p. 2746 - 2749 (2014/03/21)
A highly efficient one-pot procedure for the preparation of 1-chloroalkynes and 1-chlorobutadiynes from terminal and trialkylsilyl-protected precursors is reported. This convenient reaction, proceeding under mild conditions, utilizes N-chlorosuccinimide as the chlorinating agent and tolerates a range of functional groups. A general chlorination of alkynes: A highly efficient one-pot procedure for the preparation of 1-chloroalkynes and 1-chlorobutadiynes from terminal and trialkylsilyl-protected precursors is reported (see figure; TMS=trimethylsilyl, TES=triethylsilyl, TBDMS=tert-butyldimethylsilyl, TIPS=triisopropylsilyl). This convenient reaction, proceeding under mild conditions, utilizes N-chlorosuccinimide as the chlorinating agent and tolerates a range of functional groups.
Copper catalyzed decarboxylative alkynylation of quaternary α-cyano acetate salts
Feng, Yi-Si,Xu, Zhong-Qiu,Mao, Long,Zhang, Feng-Feng,Xu, Hua-Jian
supporting information, p. 1472 - 1475 (2013/06/27)
Cu-catalyzed decarboxylative alkynylation of quaternary α-cyano acetate salts with alkynyl bromides and alkynyl chlorides is described. This new reaction can be used for preparing functionalized butynenitrile derivatives.
