7716-86-1Relevant 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.
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.).
Electrochemical synthesis of α,α-dihaloacetophenones from terminal alkyne derivatives
Li, Zhibin,Sun, Qi,Qian, Peng,Hu, Kangfei,Zha, Zhenggen,Wang, Zhiyong
supporting information, p. 1855 - 1858 (2020/03/10)
By virtue of electrochemistry, a series of α,α-dihaloacetophenones were easily obtained with good to excellent yields. This electrochemical procedure was taken in a divided cell with constant current in aqueous media. The reaction can be carried out smoothly at room temperature under metal and oxidant free condition, which provides an eco-friendly synthesis for the α,α-dihaloacetophenone derivatives.
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.
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.
Ultrasound-assisted tandem reaction of alkynes and trihaloisocyanuric acids by thiourea as catalyst in water
Zhang, Xingyu,Wu, Yundong,Zhang, Ya,Liu, Huilan,Xie, Ziyu,Fu, Shengmin,Liu, Fang
, p. 4513 - 4518 (2017/07/10)
With water as the sole solvent, a green and efficient method has been developed for the synthesis of various α,α-dihaloketones via ultrasound assisted p-tolylthiourea catalyzed tandem reaction of alkynes with trihaloisocyanuric acids. This synthetic route
A Simple and Efficient Method for the Preparation of α-Halogenated Ketones Using Iron(III) Chloride and Iron(III) Bromide as Halogen Sources with Phenyliodonium Diacetate as Oxidant
Tang, Shi-Zhong,Zhao, Wenshuang,Chen, Tao,Liu, Yang,Zhang, Xiao-Ming,Zhang, Fu-Min
supporting information, p. 4177 - 4183 (2017/12/18)
α-Halogenated ketones are both unique structure moieties existing in biologically natural products and valuable synthetic intermediates for the preparation of functional molecules. An efficient and scalable method for the preparation of α-halogenated ketone using iron (III) chloride and iron (III) bromide as halogen sources with phenyliodonium diacetate as oxidant has been developed, featuring mild reaction conditions, environmentally friendly reagents, and wide substrate scope. Notably, the three-step synthesis of drug prasugrel was achieved using this developed method as a key step with 30% yield on gram-scale. Additionally, the reaction mechanism involving chloride cation was proposed based on some preliminary control experiments. (Figure presented.).
N-Chloro-N-methoxybenzenesulfonamide: A Chlorinating Reagent
Pu, Xiaoqiu,Li, Qingwei,Lu, Zehai,Yang, Xianjin
supporting information, p. 5937 - 5940 (2016/12/26)
A structurally simple and reactive chlorinating reagent, N-chloro-N-methoxybenzenesulfonamide, was conveniently and economically prepared in high yield. 1,3-Diketones, β-keto esters, benzoyl trifluoroacetones, phenols, anisoles, heteroarenes, and aromatic amines were successfully chlorinated, and the products were obtained in good to high yields.
A simple, mild, and efficient method for the preparation of α,α-dichloroketones with DCDMH catalyzed by ammonium chloride
Zheng, Zubiao,Han, Bingbing,Cheng, Peng,Niu, Jiangxiu,Wang, Aidong
, p. 9814 - 9818 (2015/01/09)
New process that can selectively prepare α,α-dichloro ketones from various ketones with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) using ammonium chloride as a catalyst is reported. The effects of ammonium salts, solvents, DCDMH, and reaction temperature were investigated. Under the optimal condition, most of α,α-dichlorinated products were selectively obtained in 86-98% yield.
