- Access to α,α-dihaloacetophenones through anodic C[dbnd]C bond cleavage in enaminones
-
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.
- Zhang, Zhenlei,Yang, Jiusi,Wu, Kairui,Yu, Renjie,Bu, Jiping,Huang, Zijun,Li, Shaoke,Ma, Xiantao
-
-
- Method for preparing alpha,alpha-dichloroketone under solvent-free condition
-
The invention provides a method for synthesizing an alpha,alpha-dichloroketone compound by taking methyl ketone and sulfonyl chloride as raw materials. The method comprises the following steps: heating a reaction mixture of methyl ketone and sulfonyl chloride to 80 DEG C under a dry air condition, stirring for 4-8 hours, after the reaction is finished, removing sulfonyl chloride from the obtained mixture, and carrying out silica gel column chromatography separation by taking ethyl acetate-hexane as an eluent to obtain the alpha,alpha-dichloroketone compound. The synthesis method provided by the invention has the advantages of extremely high chemical reactivity and selectivity, simple and easily available raw materials, low price, simple operation, no need of any catalyst and solvent, reduction of the synthesis cost and the pollution of organic solvents to the environment, greenness, economy and the like.
- -
-
Page/Page column 5
(2021/06/21)
-
- Solvent-free preparation of α,α-dichloroketones with sulfuryl chloride
-
An efficient and facile method is reported for the synthesis of a series of α,α-dichloroketones. The direct dichlorination of methyl ketones and 1,3-dicarbonyls using an excess amount of sulfuryl chloride affords the corresponding gem-dichloro compounds in moderate to excellent yields. Moreover, the protocol features high yields, broad substrate scope, and simple reaction conditions without using any catalysts and solvents.
- Tu, Dewei,Luo, Juan,Jiang, Wengao,Tang, Qiang
-
supporting information
(2021/09/15)
-
- Electrochemical synthesis of α,α-dihaloacetophenones from terminal alkyne derivatives
-
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.
- Li, Zhibin,Sun, Qi,Qian, Peng,Hu, Kangfei,Zha, Zhenggen,Wang, Zhiyong
-
supporting information
p. 1855 - 1858
(2020/03/10)
-
- Electrochemical Oxidative Oxydihalogenation of Alkynes for the Synthesis of α,α-Dihaloketones
-
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.
- Meng, Xiangtai,Zhang, Yu,Luo, Jinyue,Wang, Fei,Cao, Xiaoji,Huang, Shenlin
-
supporting information
p. 1169 - 1174
(2020/02/04)
-
- Switchable Synthesis of α,α-Dihalomethyl and α,α,α-Trihalomethyl Ketones by Metal-Free Decomposition of Enaminone C=C Double Bond
-
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.).
- Liu, Yunyun,Xiong, Jin,Wei, Li,Wan, Jie-Ping
-
supporting information
p. 877 - 883
(2020/01/24)
-
- Iodine-DMSO-promoted divergent reactivities of arylacetylenes
-
An unprecedented set of efficient, economical, atom-economic and exceedingly selective I2-DMSO-promoted methods is described for the generation of different structures. The reaction represents the first of its kind, involving the use of different iodine concentrations, temperatures, acids and salt to adjust the selectivity for the synthesis of different alkenes, α-functionalized ketones and α-ketomethylthioesters.
- Rather, Suhail A.,Kumar, Atul,Ahmed, Qazi Naveed
-
supporting information
p. 4511 - 4514
(2019/04/26)
-
- Preparation method of alpha, alpha-dichloroacetophenone compound
-
The invention discloses a preparation method of an alpha, alpha-dichloroacetophenone compound. The preparation method comprises the step of preparing the alpha, alpha-dichloroacetophenone compound ina microchannel reactor by taking an acetophenone compoun
- -
-
Paragraph 0028; 0029; 0030
(2019/04/27)
-
- Dichloroacetophenones targeting at pyruvate dehydrogenase kinase 1 with improved selectivity and antiproliferative activity: Synthesis and structure-activity relationships
-
Dichloroacetophenone is a pyruvate dehydrogenase kinase 1 (PDK1) inhibitor with suboptimal kinase selectivity. Herein, we report the synthesis and biological evaluation of a series of novel dichloroacetophenones. Structure-activity relationship analyses (SARs) enabled us to identify three potent compounds, namely 54, 55, and 64, which inhibited PDK1 function, activated pyruvate dehydrogenase complex, and reduced the proliferation of NCI-H1975 cells. Mitochondrial bioenergetics assay suggested that 54, 55, and 64 enhanced the oxidative phosphorylation in cancer cells, which might contribute to the observed anti-proliferation effects. Collectively, these results suggested that 54, 55, and 64 could be promising compounds for the development of potent PDK1 inhibitors.
- Zhang, Shao-Lin,Yang, Zheng,Hu, Xiaohui,Tam, Kin Yip
-
supporting information
p. 3441 - 3445
(2018/09/29)
-
- Ultrasound-assisted tandem reaction of alkynes and trihaloisocyanuric acids by thiourea as catalyst in water
-
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
- Zhang, Xingyu,Wu, Yundong,Zhang, Ya,Liu, Huilan,Xie, Ziyu,Fu, Shengmin,Liu, Fang
-
p. 4513 - 4518
(2017/07/10)
-
- Pathways in the Degradation of Geminal Diazides
-
The degradation of geminal diazides is described. We show that diazido acetates are converted into tetrazoles through the treatment with bases. The reaction of dichloro ketones with azide anions provides acyl azides, through in situ formation of diazido ketones. We present experimental and theoretical evidence that both fragmentations may involve the generation of acyl cyanide intermediates. The controlled degradation of terminal alkynes into amides (by loss of one carbon) or ureas (by loss of two carbons) is also shown.
- Holzschneider, Kristina,H?ring, Andreas P.,Haack, Alexander,Corey, Daniel J.,Benter, Thorsten,Kirsch, Stefan F.
-
p. 8242 - 8250
(2017/08/14)
-
- Method for removal of methanamide by dichlorination
-
A method for removal of methanamide by dichlorination is disclosed, according to the method, a finished product is obtained by removal of methanamide by dichlorination by one-step-reaction of various beta-carbonyl amide derivatives as raw materials, 2,2,6,6-Tetramethylpiperidinooxy (TEMPO) and an alkali as additives and N-chlorosuccinimide as a reagent in a reaction solvent, and then concentration and purification. According to the method, synthesis of an alpha-dichloroacetophenone derivative can be realized for the first time by a method of removal of methanamide by fracturation of carbon-carbon single bond. The method is novel and unique, has certain universality, is mild in reaction conditions, low in requirement of production equipment, and simple in technology, has the advantages of high efficiency, simple operation, high safety, economy and environmentally-friendliness; high-quality diverse alpha-dichloroacetophenone derivative products can be prepared by the method, and the products prepared by the method are important drug synthesis intermediates and material intermediates, can be widely used in the synthesis of heterocycles, unsaturated acids, acetylene alcohols and other compounds and cyclopropanation, and have wide market prospects.
- -
-
Paragraph 0020-0049; 0060-0064
(2017/10/12)
-
- One-pot dichlorinative deamidation of primary β-ketoamides
-
An approach to the dichlorinative deamidation of primary β-ketoamides through ketonic cleavage is described, and a series of α,α-dichloroketones were furnished mostly in the presence of TEMPO. Based on control experiments, a mechanism involving tandem dichlorination and deamidation is proposed to interpret the observed reactivity.
- Zheng, Congke,Zhang, Xiaohui,Ijaz Hussain, Muhammad,Huang, Mingming,Liu, Qing,Xiong, Yan,Zhu, Xiangming
-
supporting information
p. 574 - 577
(2017/01/16)
-
- A novel β-(oxy)alkyl radical during copper(I)-mediated stereoselective synthesis of (Z)-ene-1,4-diones in a reaction of 2,2,2-trichloro-1-phenylethanone
-
A novel β-(oxy)alkyl radical derived from trichloro methyl compound containing neither a suitably located C-C multiple bond nor a leaving group or a H-atom at the β-position of the radical in a reaction of 2,2,2-trichloro-1-phenyl-ethanone with 2 mol equiv each of CuCl and bpy in refluxing DCE under a N2 atm underwent intramolecular heterolysis (just like formation of intact radical cation-anion pair) during stereoselective radical dimerization to Z-ene-1,4-dione along with small amount of reductive dechlorination product. The stereochemistry was established by X-ray diffraction spectroscopy of various solid crystalline products.
- Ram, Ram N.,Tittal, Ram K.
-
supporting information
p. 2437 - 2440
(2016/05/19)
-
- Efficient and simple preparation of functionalized 1,1-dibromoenol phosphates
-
The preparation of functionalized 1,1-dibromoalkenyl phosphates is described. The protocol developed for their preparation is based on the generation of enolates from α,α-dibromoketones followed by a reaction with dialkyl chlorophosphates. The procedure t
- Kotek, Vladislav,Polk, Peter,Tobrman, Tom
-
p. 405 - 412
(2016/02/16)
-
- Grignard-mediated reduction of 2,2,2-trichloro-1-arylethanones
-
2,2,2-Trichloro-1-aryl-ethanones can be reduced by RMgX to the corresponding 2,2-dichloro-1-arylethen-1-olates and trapped with a range of electrophiles resulting in either reduction, reduction/aldol, reduction/Claisen condensation or reduction/aldol-Tishchenko products. In addition we demonstrate that 2,2-dichloro-1-arylethen-1-olates undergo counter-ion controlled Darzens condensations, which can be followed by a thermal rearrangement as a route to 1,3-diaryl-3-chloropropane-1,2-diones.
- Essa, Ali H.,Lerrick, Reinner I.,?ift?i, E?e,Harrington, Ross W.,Waddell, Paul G.,Clegg, William,Hall, Michael J.
-
p. 5793 - 5803
(2015/05/27)
-
- K 2S 2O 8-mediated difunctionalization of C≡C bonds in water: A simple and efficient approach to α, α -dihaloacetophenones from phenylacetylenes and NaX
-
A novel K2S2O8-mediated oxy-1,1-dihalogenation of alkynes with NaX in the presence of water has been developed, affording α,α-dihaloacetophenones in moderate to good yields. The advantages of this reaction are mild reaction conditions, operational simplicity, and use of pure water as reaction medium. A plausible reaction mechanism is proposed on the basis of mechanistic studies.
- Wang, Jing-Yu,Jiang, Qing,Guo, Can-Cheng
-
supporting information
p. 3130 - 3138
(2015/10/12)
-
- A simple, mild, and efficient method for the preparation of α,α-dichloroketones with DCDMH catalyzed by ammonium chloride
-
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.
- Zheng, Zubiao,Han, Bingbing,Cheng, Peng,Niu, Jiangxiu,Wang, Aidong
-
p. 9814 - 9818
(2015/01/09)
-
- A new and efficient method for the synthesis of α,α- dihaloketones by oxyhalogenation of alkynes using oxone-KX (X = Cl, Br, or I)
-
A simple and efficient method for the preparation of α,α- dichloroketones, α,α-dibromoketones, and α,α- diiodoketones by oxyhalogenation of alkynes using oxone and KX (X = Cl, Br, or I) is described.
- Madabhushi, Sridhar,Jillella, Raveendra,Mallu, Kishore Kumar Reddy,Godala, Kondal Reddy,Vangipuram, Venkata Sairam
-
supporting information
p. 3993 - 3996
(2013/07/25)
-
- Reduction of 2,2,2-trichloro-1-arylethanones by RMgX: Mechanistic investigation and the synthesis of substituted α,α-dichloroketones
-
2,2,2-Trichloro-1-arylethanones undergo high yielding reductions to the corresponding 2,2-dichloro-1-arylethanones in the presence of RMgX. A single electron transfer mechanism for the reaction is proposed based on trapping experiments. Reaction of the intermediate enolates with a range of electrophiles is described, providing a convenient route to substituted α,α- dichloro-β-hydroxyketones and related molecules. The Royal Society of Chemistry 2013.
- Essa, Ali H.,Lerrick, Reinner I.,Tuna, Floriana,Harrington, Ross W.,Clegg, William,Hall, Michael J.
-
p. 2756 - 2758
(2013/04/23)
-
- One-step conversion of acetophenones to α-haloacetophenone dimethyl acetals using DCDMH/DBDMH and molecular sieve in methanol
-
Using DCDMH/DBDMH as N-halo reagent, piperidine as catalyst, and 4-A molecular sieve as water-removing agent, α-haloacetophenone dimethyl acetals were directly obtained from the solvent of methanol. As to the substrates with electronwithdrawing groups, the conversions were 80-100%. Copyright Taylor & Francis Group, LLC.
- Zhou, Bin,Chen, Zizhan,Zheng, Zubiao,Han, Bingbing,Zou, Xinzhuo
-
experimental part
p. 1445 - 1453
(2012/04/17)
-
- α-Halogenation of carbonyl compounds: Halotrimethylsilane-nitrate salt couple as an efficient halogenating reagent system
-
A mixture of chloro/bromotrimethylsilane and nitrate salt is found to be an effective reagent system for the α-chlorination/bromination of carbonyl compounds. The reaction occurs under mild conditions yielding the products in moderate to good yields.
- Prakash, G.K. Sxurya,Ismail, Rehana,Garcia, Jessica,Panja, Chiradeep,Rasul, Golam,Mathew, Thomas,Olah, George A.
-
experimental part
p. 1217 - 1221
(2011/03/22)
-
- Simple and efficient methods for selective preparation of α-mono or α,α-dichloro ketones and β-ketoesters by using DCDMH
-
New processes that can selectively prepare α-mono or α,α-dichloro ketones and β-ketoesters using 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) are reported. Using silica gel as the catalyst and methanol as the solvent and heating for 1 h under reflux, α-monochlorinated products were selectively obtained in 86-98% yield. However using a deep eutectic solvent (choline chloride: p-TsOH = 1:1) as the solvent and stirring for 45 min at room temperature, α,α- dichlorinated products were selectively obtained in 86-95% yield.
- Chen, Zizhan,Zhou, Bin,Cai, Huihua,Zhu, Wei,Zou, Xinzhuo
-
experimental part
p. 275 - 278
(2010/04/22)
-
- Cu(OTf)2-catalyzed α-halogenation of ketones with 1,3-dichloro-5,5'-dimethylhydantoin and N-bromosuccinimide
-
Copper(II) triflate catalyses efficiently the α-halogentaion of aryl or alkyl ketones with l.3-diehloro-5.5'-dimethylhydantoin and N-bromosuccinimde to give the corresponding α,α-dichloroketones and α-bromoketones in high yield with excellent product selectivity.
- Jagdale, Arun R.,Chouthaiwale, Pandurang V.,Sudalai, Arumugam
-
experimental part
p. 1424 - 1430
(2010/02/28)
-
- A convenient and efficient synthesis of 1-aryl-2,2-dichloroethanones
-
1-Arylethanones are readily chlorinated with an aqueous HCl-H 2O2 system using ethanol as a cosolvent. The reaction prceeds rapidly and results in selective conversion of 1-arylethanones into 1-aryl-2,2-dichloroethanones in yields of 48-89%, depending on the nature of the substituent in the aryl group.
- Terent'ev, Alexander O.,Khodykin, Sergey V.,Troitskii, Nikolay A.,Ogibin, Yuri N.,Nikishin, Gennady I.
-
p. 2845 - 2848
(2007/10/03)
-
- Selective preparation of α,α-dichloroketones with copper(II) chloride
-
Aryl and enolizable alkyl ketones react with copper(II) chloride in dimethylformamide to produce the corresponding α,α-dichloroketone in high yields. Remarkable qualities of the process are high selectivity towards these substrates, undetected polychlorinated by-products, easy work-up, commercially available reagents and HCl as the only waste stream.
- Nobrega, Jose Arimateia,Goncalves, Simone Maria C.,Peppe, Clovis
-
p. 3711 - 3717
(2007/10/03)
-
- Processes for producing 1-substituted-2-cyanoimidazole compounds
-
A process for producing 1-substituted-2-cyanoimidazole compounds is described, which comprises (1) undergoing a reaction of a compound represented by formula (IV), hydroxylamine or a mineral acid salt thereof, and glyoxal or glyoxime to produce a compound represented by formula (III), (2) undergoing a reaction of the compound represented by formula (III) with thionyl chloride or thionyl bromide in the presence of N,N-dialkylamide to produce a reaction mixture, and then reacting the produced reaction mixture with sulfur chloride to produce a 2-cyanoimidazole compound represented by formula (II), and (3) undergoing a sulfamoylation reaction and an isomerization reaction of the 2-cyanoimidazole compound represented by formula (II) and a compound represented by formula (V) in the presence of at least one base selected from carbonates of alkali metals and bicarbonates of alkali metals and a polar solvent to produce a 1-substituted-2-cyanoimidazole compound represented by formula (I-b). The formulae and substituents formulae are specifically defined in the specification. STR1
- -
-
-
- Reactions of 1-aryl-2,2-dihalogenoethanone oximes with tetrasulfur tetranitride (S4N4): A general method for the synthesis of 3-aryl-4-halogeno-1,2,5-thiadiazoles
-
1-Aryl-2,2-dichloro-7, 1-aryl-2,2-dibromo-8, 1-aryl-2-bromo-2-fluoro-9 and 1-aryl-2-chloro-2-fluoroethanone oximes 10 have been prepared by allowing the corresponding ketones to react with hydroxylamine hydrochloride in EtOH at room temperature. Stereoche
- Yoon, Sung Cheol,Cho, Jaeeock,Kim, Kyongtae
-
p. 109 - 116
(2007/10/03)
-
- Halogenation Using Quaternary Ammonium Polyhalides. XXXII. Dichlorination of Aromatic Acetyl Derivatives with Benzyltrimethylammonium Tetrachloroiodate
-
The reaction of aromatic acetyl derivatives with 2 molar amounts of benzyltrimethylammonium tetrachloroiodate in acetic acid at 70 deg C for several hours gave dichloroacetyl derivatives in good yields.
- Kakinami, Takaaki,Urabe, Yasuaki,Hermawan, Irwan,Yamanishi, Hiroko,Okamoto, Tsuyoshi,Kajigaeshi, Shoji
-
p. 2549 - 2551
(2007/10/02)
-
- A New Synthetic Route to Aromatic Gyloxals
-
Dichloroacylation of toluene, o- and m- xylenes, chloro- and bromo-benzenes and m-chlorotoluene under Friedel-Crafts conditions leads to the corresponding chloroketones (Ia-f) which on controlled hydrolysis afford the glyoxals (IIa-f) respectively.
- Mahato, S. B.,Podder, G.,Maitra, S. K.
-
-
- REACTION DE L'ACIDE PERCHLORIQUE SUR LES PHENYLACETYLENES SUBSTITUES. MISE EN EVIDENCE D'UN MECANISME IONIQUE ET RADICALAIRE
-
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.
- Montheard, Jean-Pierre,Camps, Marcel,Benzaid, Ahmed,Pascal, Jean-Louis
-
p. 3483 - 3486
(2007/10/02)
-
- Molecular Rearrangements. 13. Kinetics and Mechanism of Rearrangements of Some Ring-Substituted α-Chlorostyrene Oxides and trans-β-Chlorostyrene Oxides.
-
The synthesis of certain phenyl-substituted derivatives of the isomeric trans-β-chlorostyrene oxides (6) and α-chlorostyrene oxides (7) are reported.The kinetics of rearrangement of 6 (X = p-CH3, H, p-Br, m-Cl, p-NO2) to phenylchloroacetaldehydes (12) in CCl4 buffered by Na2HPO4 and 7 (X = p-CH3, H, p-NO2) to ω-chloroacetophenones in CCl4 were determined by following the rates of disappearance of the α-chloro epoxide and formation of the α-chloro carbonyl product.These substituent effects at 130 deg C were correlated with ?+ constants, yielding ρ values of-3.5 and -0.57 for the rearrangements of 6 and 7, respectively.In nitrobenzene solvent, the kC6H5NO2/kCCl4 for 6 was 180 and for 7 was 1740, the latter solvent effect attributed to nucleophilic solvent participation.It was concluded that these thermal rearrangements of 6 and 7 occur by disrotatory Cβ-O bond heterolysis to yield the corresponding α-keto carbonium-chloride ion pairs.
- McDonald, Richard N.,Cousins, Raymond C.
-
p. 2976 - 2984
(2007/10/02)
-
- Photoinduced Alcoholysis of the Trichloroacetyl Group
-
Irradiation of α,α,α-trichloroacetophenone (1a) in methanol afforded alcoholysis products methyl benzoate (2; X=H, R=Me) and methyl benzoylformate (3; X=H, R=Me) along with dichloroacetophenone.Formation of 2 was greatly favored in the presence of oxygen, whereas that of 3 was favored by the sensitization.Quenching studies showed that both alcoholysis products are derived from different excited triplet states.Reaction mechanisms involving the exciplex between 1 and oxygen are discussed.
- Izawa, Yasuji,Tomioka, Hideo,Natsume, Masashi,Beppu, Shinji,Tsujii, Hideo
-
p. 4835 - 4838
(2007/10/02)
-