31984-10-8Relevant articles and documents
Gold N-Heterocyclic Carbene Catalysts for the Hydrofluorination of Alkynes Using Hydrofluoric Acid: Reaction Scope, Mechanistic Studies and the Tracking of Elusive Intermediates
Bédard, Sandrine,Cavallo, Luigi,Falivene, Laura,Gauthier, Rapha?l,Nolan, Steven P.,Paquin, Jean-Fran?ois,Saab, Marina,Tzouras, Nikolaos V.,Van Hecke, Kristof,Zhang, Ziyun
supporting information, (2021/12/09)
An efficient and chemoselective methodology deploying gold-N-heterocyclic carbene (NHC) complexes as catalysts in the hydrofluorination of terminal alkynes using aqueous HF has been developed. Mechanistic studies shed light on an in situ generated catalyst, formed by the reaction of Br?nsted basic gold pre-catalysts with HF in water, which exhibits the highest reactivity and chemoselectivity. The catalytic system has a wide alkyl substituted-substrate scope, and stoichiometric as well as catalytic reactions with tailor-designed gold pre-catalysts enable the identification of various gold species involved along the catalytic cycle. Computational studies aid in understanding the chemoselectivity observed through examination of key mechanistic steps for phosphine- and NHC-coordinated gold species bearing the triflate counterion and the elusive key complex bearing a bifluoride counterion.
Selective Debromination of α,α,α-Tribromomethylketones with HBr–H2O Reductive Catalytic System
Cheng, Zhao,Guo, Hongmei,Huang, Guozheng,Rexit, Abulikemu Abudu,Wang, Hui,Zheng, Meng-Xia
, p. 6455 - 6458 (2020/10/21)
A debromination of α,α,α-tribromomethylketones is developed for chemoselective synthesis of α-mono- and α,α-dibromomethylketones with high selectivity under H2O–HBr reductive conditions. This method offers an efficient and direct way to synthesize α-mono or α,α-dibromomethylketone compounds in high to excellent yields through the process of HBr self-circulation in water.
Facile Approach to Geminal HeterodihalogenationOne-Pot Synthesis of α-Bromo-α-Chloro Ketones
Bian, Ming,Tang, Dong-Min,Zhou, Jin-Feng
supporting information, (2020/09/09)
An efficient and practical protocol for the geminal heterodihalogenation of methyl ketones by using readily available dimethyl sulfoxide and a combination of HCl and HBr is reported. Control experiments suggested that the acidity of the solution, as well as the oxidizing ability and nucleophilicity of the dimethyl sulfoxide might work cooperatively in ensuring the success of the tandem substitution. Its operational simplicity, easy accessibility, and mild oxidative conditions suggest that the present strategy might be useful for the assembly of bromochloromethyl functional groups in drug discovery.
A radical exchange process: Synthesis of bicyclo[1.1.1]pentane derivatives of xanthates
Rout, Saroj Kumar,Marghem, Gilles,Lan, Junjie,Leyssens, Tom,Riant, Olivier
supporting information, p. 14976 - 14979 (2019/12/24)
Bicyclo[1.1.1]pentane (BCP) replacement as a bioisostere in drug molecules has an influence on their permeability, aqueous solubility and in vitro metabolic stability. Thus, the chemical installation of the BCP unit into a chemical entity remains a significant challenge from a synthetic point of view. Here, we have presented a new approach for the installation of the BCP unit on the xanthate moiety by means of a radical exchange process.
3-Phenylalkyl-2H-chromenes and -chromans as novel rhinovirus infection inhibitors
Conti, Cinzia,Proietti Monaco, Luca,Desideri, Nicoletta
, p. 2074 - 2083 (2017/03/23)
Following our studies on structure-activity relationships of anti-rhinovirus chromene and chroman derivatives, we designed and synthesized new series of 3-phenylalkyl-2H-chromenes and -chromans bearing differently sized, aliphatic linker chains between the two cycles. The cytotoxicity and the antiviral activity of the new compounds on human rhinovirus (HRV) serotype 1B and 14 infection were evaluated in HeLa cell cultures. Most of the tested compounds interfered with HRV1B multiplication in the micromolar or submicromolar concentrations while HRV14 was less susceptible. 3-[3-(4-Chlorophenyl)propyl]chroman (9c) was selected for preliminary mechanism of action studies due to its potent activity against both serotypes (IC50 of 0.48?μM and 1.36?μM towards HRV1B and 14, respectively) coupled with high selectivity (SI?=?206.18 and 73.26, respectively). Results of time of addition/removal studies suggest that 9c, similarly to related derivatives, behaves as a capsid binder interfering with some early events of the HRV1B infectious cycle.
Novel method for preparing Prostaglandin derivatives
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Paragraph 0093; 0094-0097, (2017/10/31)
Provided is a novel method for preparing prostaglandin derivatives. The method is suitable for mass production by effectively manufacturing prostaglandin derivatives with high yield. The method comprises the following steps: (S-1) adding a first reducing agent to a prostaglandin intermediate compound represented by chemical formula II and manufacturing a compound represented by chemical formula III; (S-2) manufacturing a compound represented by chemical formula IV from the compound represented by chemical formula III in the presence of a base; (S-3) adding a second reducing agent to the compound represented by chemical formula IV and manufacturing a compound represented by chemical formula V; and (S-4) performing Wittig reaction of the compound represented by chemical formula V and a compound represented by chemical formula VI, and manufacturing a compound represented by chemical formula I.COPYRIGHT KIPO 2017
A new synthetic approach to prostaglandin analogues: Synthesis of bimatoprost via lipase enzymatic catalysis
Kamidi, Vijendhar,Kale, Pooja,Boodida, Sathyanarayana
, p. 2767 - 2770 (2017/11/10)
A simple, convenient and efficient synthetic approach for the synthesis of (15S) bimatoprost (4) via lipase enzyme mediated stereo selective reduction from chiral precursor Corey lactone diol as substrate was described. Swern oxidation, lipase enzymatic reduction and Wittig reaction conditions are used as key steps for the synthesis of bimatoprost. This method was found to be an efficient with considerable yield, cost effective and minimized the synthetic steps compared to reported procedures.
Highly Efficient Synthesis of α-Halomethylketones via Ce(SO4)2/Acid Co-Catalyzed Hydration of Alkynes
Zou, Huaxu,Jiang, Jun,Yi, Niannian,Fu, Wenqiang,Deng, Wei,Xiang, Jiannan
supporting information, p. 1251 - 1254 (2016/12/27)
A general atom-economical approach for the synthesis of α-halomethyl ketones is demonstrated through Ce(SO4)2/acid co-catalyzed hydration of a wide range of haloalkynes. The reactions are conducted under convenient conditions and provide products with excellent regioselectivity in good to excellent yields, with broad substrate scope. This protocol is an alternative to conventional α-halogenation of ketones.
In(OTf)3/acid co-catalyzed hydration of 1-haloalkynes to α-halomethyl ketones
Zeng, Ming,Huang, Rui-Xue,Li, Wen-Yi,Liu, Xiao-Wen,He, Fu-Ling,Zhang, Yi-Yuan,Xiao, Fang
, p. 3818 - 3822 (2016/07/06)
A novel and efficient In(OTf)3and HOAc cooperatively catalyzed hydration of 1-haloalkynes is described. This method provides ready access to α-chloromethyl ketones, α-bromomethyl ketones and α-iodomethyl ketones in moderate to high yields from simple, inexpensive starting materials. A broad substrate scope is achieved, and the reaction is compatible with various functional groups, including alkoxy, trifluoromethyl, halide, hydroxyl, cyclohexyl, and heterocyclic groups.
First Catalyzed Hydration of Haloalkynes by a Recyclable Catalytic System
Zou, Huaxu,He, Weibao,Dong, Qizhi,Wang, Ruijia,Yi, Niannian,Jiang, Jun,Pen, Dongming,He, Weimin
, p. 116 - 121 (2016/01/26)
The hydration of haloalkynes to give α-halomethyl ketones was achieved based on a combination of a Cu(OAc)2 catalyst and a TFA (trifluoroacetic acid) promoter. This is the first synthesis of chloro/bromo/iodo methyl ketones through a hydration reaction catalyzed by a recyclable catalytic system. The catalytic system has a wide substrate scope and excellent chemoselectivity, and the procedure can also be scaled up.