21566-36-9Relevant academic research and scientific papers
Access to α,α-dihaloacetophenones through anodic C[dbnd]C bond cleavage in enaminones
Zhang, Zhenlei,Yang, Jiusi,Wu, Kairui,Yu, Renjie,Bu, Jiping,Huang, Zijun,Li, Shaoke,Ma, Xiantao
, (2021/12/20)
We have developed a method to synthesize α,α-dihaloketones under electrochemical conditions. In this reaction, the Cl- or Br- is oxidized to Cl2 or Br2 at the anode, which undergoes two-step addition reactions with the N,N-dimethyl enaminone, and finally breaks C[dbnd]C of the N,N-dimethyl enaminone to generate α,α-dihaloketones. The electrosynthesis reaction can be conveniently carried out in an undivided electrolytic cell at room temperature. In addition, various functional groups are compatible with this green protocol which can be applied simultaneously to the gram scale without significantly lower yield.
Electrochemical Oxidative Oxydihalogenation of Alkynes for the Synthesis of α,α-Dihaloketones
Meng, Xiangtai,Zhang, Yu,Luo, Jinyue,Wang, Fei,Cao, Xiaoji,Huang, Shenlin
supporting information, p. 1169 - 1174 (2020/02/04)
An electrochemical oxydihalogenation of alkynes has been developed for the first time. Using this sustainable protocol, a variety of α,α-dihaloketones can be prepared with readily available CHCl3, CH2Cl2, ClCH2CH2Cl, and CH2Br2 as the halogen source under electrochemical conditions at room temperature.
α,α-Dibromoketone precursors in the synthesis of some new thiazole derivatives: Thiazol-2-yl hydrazonobutanoates, thiazol-2-yl pyrazole-4-carboxylates and acids
Joshi, Radhika,Kiran, Vijay,Pundeer, Rashmi
supporting information, (2020/03/04)
In the present study, α,α-dibromoacetophenones are used as efficient precursors for the facile synthesis of several new hydrazonothiazoles, ethyl 3-((4-arylthiazol-2-yl)hydrazono)butanoates, which undergo Vilsmeier-Haack cyclization to obtain thiazolylpyrazole esters, ethyl 3-methyl-1-(4-arylthiazol-2-yl)-1H-pyrazole-4-carbxylates, basic hydrolysis of which gives the corresponding acids, 3-methyl-1-(4-arylthiazol-2-yl)-1H-pyrazole-4-carbxylic acids. All these compounds are tested for antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis; Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa and antifungal activity against Saccharomyces cerevisiae and Candida albicans.
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.
Switchable Synthesis of α,α-Dihalomethyl and α,α,α-Trihalomethyl Ketones by Metal-Free Decomposition of Enaminone C=C Double Bond
Liu, Yunyun,Xiong, Jin,Wei, Li,Wan, Jie-Ping
supporting information, p. 877 - 883 (2020/01/24)
The novel free radical-based cleavage of the enaminone C=C double bond is realized by using N-halosuccinimides (NXS) in the presence of benzoyl peroxide (BPO) with mild heating, enabling the tunable synthesis of α,α-dihalomethyl ketones and α,α,α-trihalomethyl ketones under different reaction conditions. The formation of these divergent products involving featured C=C double bond cleavage requires no any metal reagent, and represents one more practical example on the synthesis of poly halogenated methyl ketones via the functionalization of carbon?carbon bond. (Figure presented.).
Visible-light-promoted oxidative halogenation of alkynes
Li, Yiming,Mou, Tao,Lu, Lingling,Jiang, Xuefeng
supporting information, p. 14299 - 14302 (2019/12/02)
In nature, halogenation promotes the biological activity of secondary metabolites, especially geminal dihalogenation. Related natural molecules have been studied for decades. In recent years, their diversified vital activities have been explored for treating various diseases, which call for efficient and divergent synthetic strategies to facilitate drug discovery. Here we report a catalyst-free oxidative halogenation achieved under ambient conditions (halide ion, air, water, visible light, room temperature, and normal pressure). Constitutionally, electron transfer between the oxygen and halide ion is shuttled via simple conjugated molecules, in which phenylacetylene works as both reactant and catalyst. Synthetically, it provides a highly compatible late-stage transformation strategy to build up dihaloacetophenones (DHAPs).
Micelle-Enabled Photoassisted Selective Oxyhalogenation of Alkynes in Water under Mild Conditions
Finck, Lucie,Brals, Jeremy,Pavuluri, Bhavana,Gallou, Fabrice,Handa, Sachin
, p. 7366 - 7372 (2018/07/29)
Using micelles of FI-750-M, visible light, photocatalysts, and inexpensive halogenating reagents, such as N-bromosuccinimide and N-chlorosuccinimde, selective oxyhalogenations of alkynes were achieved in water under very mild conditions. No halogenation at the aromatic rings was detected, and control experiments revealed the radical pathway. The easily conducted protocol exhibited high reproducibility, was readily adjusted to gram scale, and allowed for recycling of reaction medium and catalyst.
Preparation method of alpha, alpha-dibromoketone
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Paragraph 0021-0023, (2018/04/21)
The invention belongs to the field of preparation of fine chemical products and synthesis of pharmaceutical intermediates and relates to a preparation method of novel alpha, alpha-dibromoketone, in particular to a method for converting olefin into alpha, alpha-dibromoketone by use of dibromohydantoin or N-bromosuccinimide. Compared with the reported methods, the method has the advantages that rawmaterials are easy to obtain and low in cost, used reagents have smaller toxicity, and the method has greater cost and environmental protection advantages and wide application prospects.
High-Potency Phenylquinoxalinone Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Activators
Son, Jung-Ho,Zhu, Jie S.,Phuan, Puay-Wah,Cil, Onur,Teuthorn, Andrew P.,Ku, Colton K.,Lee, Sujin,Verkman, Alan S.,Kurth, Mark J.
, p. 2401 - 2410 (2017/04/03)
We previously identified phenylquinoxalinone CFTRact-J027 (4) as a cystic fibrosis transmembrane conductance regulator (CFTR) activator with an EC50 of ～200 nM and demonstrated its therapeutic efficacy in mouse models of constipation. Here, structure-activity studies were done on 36 synthesized phenylquinoxalinone analogs to identify compounds with improved potency and altered metabolic stability. Synthesis of the phenylquinoxalinone core was generally accomplished by condensation of 1,2-phenylenediamines with substituted phenyloxoacetates. Structure-activity studies established, among other features, the privileged nature of a properly positioned nitro moiety on the 3-aryl group. Synthesized analogs showed improved CFTR activation potency compared to 4 with EC50 down to 21 nM and with greater metabolic stability. CFTR activators have potential therapeutic indications in constipation, dry eye, cholestatic liver diseases, and inflammatory lung disorders.
Lewis acid catalyzed cascade annulation of alkynols with α-ketoesters: A facile access to γ-spiroketal-γ-lactones
Kambale, Digambar A.,Thorat, Sagar S.,Pratapure, Madhukar S.,Gonnade, Rajesh G.,Kontham, Ravindar
supporting information, p. 6641 - 6644 (2017/07/10)
A novel Lewis acid catalyzed intermolecular cascade annulation of alkynols with α-ketoesters has been developed. This simple and efficient cascade annulation proceeds through a 5-exo-dig cyclization of alkynols followed by annulation with α-ketoester to provide a wide variety of unsaturated γ-spiroketal-γ-lactones (1,6-dioxaspiro[4.4]non-3-en-2-ones) related to many natural products.
