- Asymmetric Transfer Hydrogenation of Diaryl Ketones with Ethanol Catalyzed by Chiral NCP Pincer Iridium Complexes
-
The use of a chiral (NCP)Ir complex as the precatalyst allowed for the discovery of asymmetric transfer hydrogenation of diaryl ketones with ethanol as the hydrogen source and solvent. This reaction was applicable to various ortho-substituted diaryl keontes, affording benzhydrols in good yields and enantioselectivities. This protocol could be carried out in a gram scale under mild reaction conditions. The utility of the catalytic system was highlighted by the synthesis of the key precursor of (S)-neobenodine.
- Huang, Zheng,Liu, Guixia,Qian, Lu,Tang, Xixia,Wang, Yulei
-
supporting information
(2022/02/23)
-
- Mechanochemical Solvent-Free Suzuki–Miyaura Cross-Coupling of Amides via Highly Chemoselective N?C Cleavage
-
Although cross-coupling reactions of amides by selective N?C cleavage are one of the most powerful and burgeoning areas in organic synthesis due to the ubiquity of amide bonds, the development of mechanochemical, solid-state methods remains a major challe
- Ma, Yangmin,Shao, Lei,Szostak, Michal,Wang, Ruihong,Zhang, Jin,Zhang, Pei
-
supporting information
(2022/01/04)
-
- Preparation method of benzophenone derivative
-
The invention provides a preparation method of a benzophenone derivative. The preparation method comprises the following step: subjecting a benzoic acid compound as shown in a formula I, a trichlorotoluene compound as shown in a formula II and a benzene compound as shown in a formula III to reacting under the catalysis of Fe2O3 to obtain the benzophenone derivative. According to the preparation method provided by the invention, the metal oxide Fe2O3 with higher stability and safety is used as a catalyst, so corrosion of materials to equipment is avoided, and the preparation method is more environment-friendly; according to the preparation method, the target product is obtained through one-step reaction, reaction conditions are mild, and a process is simple; and the main byproduct benzoic acid compound generated by the reaction can be recycled by washing, extracting and desolventizing in post-treatment, and then is used as a reaction raw material for preparing the benzophenone derivative again, so wastewater treatment cost is reduced, and resources are fully utilized.
- -
-
Paragraph 0090-0095
(2021/06/22)
-
- Transition Metal Catalyst-Free, Base-Promoted 1,2-Additions of Polyfluorophenylboronates to Aldehydes and Ketones
-
A novel protocol for the transition metal-free 1,2-addition of polyfluoroaryl boronate esters to aldehydes and ketones is reported, which provides secondary alcohols, tertiary alcohols, and ketones. Control experiments and DFT calculations indicate that both the ortho-F substituents on the polyfluorophenyl boronates and the counterion K+ in the carbonate base are critical. The distinguishing features of this procedure include the employment of commercially available starting materials and the broad scope of the reaction with a wide variety of carbonyl compounds giving moderate to excellent yields. Intriguing structural features involving O?H???O and O?H???N hydrogen bonding, as well as arene-perfluoroarene interactions, in this series of racemic polyfluoroaryl carbinols have also been addressed.
- Budiman, Yudha P.,Friedrich, Alexandra,Kole, Goutam Kumar,Liu, Zhiqiang,Luo, Xiaoling,Marder, Todd B.,Radius, Udo,Tian, Ya-Ming,Westcott, Stephen A.
-
supporting information
p. 16529 - 16538
(2021/06/23)
-
- Tetra- And Dinuclear Palladium Complexes Based on a Ligand of 2,8-Di-2-pyridinylanthyridine: Preparation, Characterization, and Catalytic Activity
-
Complexation of L [L = 5-phenyl-2,8-di-2-pyridinyl-anthyridine] with [Pd(CH3CN)4](BF4)2 and [Pd(CH3CN)3Cl](BF4) in a molar ratio of 1:2 rendered the corresponding dinuclear complexes [Pd2L (CH3CN)4](BF4)4 (1) and [Pd2L (CH3CN)2Cl2](BF4)2 (2), respectively. However, treatment of L with (COD)PdCl2 followed by anion exchange yielded a tetranuclear complex [Pd4L3Cl4](PF6)4(4a). Structures of these complexes are characterized by both spectroscopy and X-ray crystallography. Interconversion of these three complexes was studied via the manipulation of stoichiometric ratio of ligand to metal precursor. The catalytic activity of these complexes for carbonylative Suzuki-Miyaura cross-coupling was investigated. Complex 2 shows an excellent catalytic activity on the reaction of aryl iodide with arylboronic acid in the presence of atmospheric pressure of CO to give the corresponding benzophenones.
- Lin, Shih-Chieh Aaron,Liu, Shiuh-Tzung,Liu, Yi-Hung,Peng, Shie-Ming,Su, Bo-Kai
-
p. 2081 - 2089
(2021/07/26)
-
- Pd-Catalysed direct C(sp2)-H fluorination of aromatic ketones: Concise access to anacetrapib
-
The Pd-cataylsed direct ortho-C(sp2)-H fluorination of aromatic ketones has been developed for the first time. The reaction features good regioselectivity and simple operations, constituting an alternative shortcut to access fluorinated ketones. A concise synthesis of anacetrapib has also been achieved by using late-stage C-H fluorination as a key step.
- Wu, Qiuzi,Mao, Yang-Jie,Zhou, Kun,Wang, Shuang,Chen, Lei,Xu, Zhen-Yuan,Lou, Shao-Jie,Xu, Dan-Qian
-
p. 4544 - 4547
(2021/05/17)
-
- Poly(ethylene glycol) dimethyl ether mediated oxidative scission of aromatic olefins to carbonyl compounds by molecular oxygen
-
A simple, and practical oxidative scission of aromatic olefins to carbonyl compounds using O2as the sole oxidant with poly(ethylene glycol) dimethyl ether as a benign solvent has been developed. A wide range of monosubstituted,gem-disubstituted, 1,2-disubstituted, trisubstituted and tetrasubstituted aromatic olefins was successfully converted into the corresponding aldehydes and ketones in excellent yields even with gram-scale reaction. Some control experiments were also conducted to support a possible reaction pathway.
- Yu, Tao,Guo, Mingqing,Wen, Simiaomiao,Zhao, Rongrong,Wang, Jinlong,Sun, Yanli,Liu, Qixing,Zhou, Haifeng
-
p. 13848 - 13852
(2021/04/22)
-
- Method for preparing aldehyde ketone compound through olefin oxidation
-
The invention provides a method for preparing an aldehyde ketone compound by olefin oxidation, which relates to an olefin oxidative cracking reaction in which oxygen participates. The method comprises the following specific steps: in the presence of a solvent and an oxidant, carrying out oxidative cracking on an olefin raw material to obtain a corresponding aldehyde ketone product. Compared with the traditional method, the method does not need to add any catalyst or ligand, does not need to use high-pressure oxygen, has the advantages of simple and mild reaction conditions, environment friendliness, low cost, high atom economy and the like, is wide in substrate application range and high in yield, and has a wide application prospect in the aspects of synthesis of aldehyde ketone medical intermediates and chemical raw materials.
- -
-
Paragraph 0019
(2021/04/07)
-
- Fe-S Catalyst Generated in Situ from Fe(III)- And S3?--Promoted Aerobic Oxidation of Terminal Alkenes
-
An iron-sulfur complex formed by the simple mixture of FeCl3 with S3?- generated in situ from K2S is developed and applied to selective aerobic oxidation of terminal alkenes. The reaction was carried out under an atmosphere of O2 (balloon) and could proceed on a gram scale, expanding the application of S3?- in organic synthesis. This study also encourages us to explore the application of an Fe-S catalyst in organic reactions.
- Ai, Jing-Jing,Huang, Cheng-Mi,Li, Jian,Liu, Bei-Bei,Rao, Weidong,Wang, Fei,Wang, Shun-Yi
-
supporting information
p. 4705 - 4709
(2021/06/28)
-
- Photo-induced oxidative cleavage of C-C double bonds for the synthesis of biaryl methanoneviaCeCl3catalysis
-
A Ce-catalyzed strategy is developed to produce biaryl methanonesviaphotooxidative cleavage of C-C double bonds at room temperature. This reaction is performed under air and demonstrates high activity as well as functional group tolerance. A synergistic Ce/ROH catalytic mechanism is also proposed based on the experimental observations. This protocol should be the first successful Ce-catalyzed photooxidation reaction of olefins with air as the oxidant, which would provide inspiration for the development of novel Ce-catalyzed photochemical synthesis processes.
- Xie, Pan,Xue, Cheng,Du, Dongdong,Shi, SanShan
-
supporting information
p. 6781 - 6785
(2021/08/20)
-
- Decatungstate-mediated solar photooxidative cleavage of CC bonds using air as an oxidant in water
-
With the increasing attention for green chemistry and sustainable development, there has been much interest in searching for greener methods and sources in organic synthesis. However, toxic additives or solvents are inevitably involved in most organic transformations. Herein, we first report the combination of direct utilization of solar energy, air as the oxidant and water as the solvent for the selective cleavage of CC double bonds in aryl olefins. Various α-methyl styrenes, diaryl alkenes as well as terminal styrenes are well tolerated in this green and sustainable strategy and furnished the desired carbonyl products in satisfactory yields. Like heterogeneous catalysis, this homogeneous catalytic system could also be reused and it retains good activity even after repeating three times. Mechanism investigations indicated that both O2- and 1O2 were involved in the reaction. Based on these results, two possible mechanisms, including the electron transfer pathway and the energy transfer pathway, were proposed.
- Du, Dongdong,Luo, Junfei,Shi, Sanshan,Xie, Pan,Xue, Cheng
-
p. 5936 - 5943
(2021/08/23)
-
- A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for aerobic oxidation of alcohols
-
A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for the aerobic oxidation of alcohols has been developed for the first time, and the photoredox aerobic oxidation of secondary and primary alcohols provided the corresponding ketones and carboxylic acids, respectively, in high to excellent yields.
- Zhu, Xianjin,Liu, Can,Liu, Yong,Yang, Haijun,Fu, Hua
-
p. 12443 - 12446
(2020/10/30)
-
- Photo-induced phosphorus radical involved semipinacol rearrangement reaction: Highly synthesis of γ-oxo-phosphonates
-
Hydroxyphosphoric acids display the unique biological activities, and they have some attractive prospects as clinical drug moleculars. Herein, a new approach for the synthesis of γ-oxo-phosphonates (the precursor of hydroxyphosphoric acid) has been established through the semipinacol rearrangement tactic involved the photo-induced phosphorus radical process. Most important, this transformation is avoid of the external oxidants, and occurs very well under the sunlight irradiation, meanwhile the γ-oxo-phosphonate was easily derivatized to obtain γ-hydroxyphosphoric acid, thus highlights the synthesis value of this method.
- Wang, Chunhai,Huang, Xiaoling,Liu, Xueting,Gao, Suqian,Zhao, Bin,Yang, Shangdong
-
supporting information
p. 677 - 680
(2019/08/27)
-
- Redox-driven deracemization of secondary alcohols by sequential ether/O2-mediated oxidation and Ru-catalyzed asymmetric reduction
-
The deracemization of benzylic alcohols has been achieved using a redox-driven one-pot two-step process. The racemic alcohols were oxidized by bis(methoxypropyl) ether and oxygen to give the ketone intermediates, followed by an asymmetric transfer hydrogenation with a chiral ruthenium catalyst. This compatible oxidation/reduction process gave the enantiomerically enriched alcohols with up to 95% ee values.
- Yang, Bing,Cui, Peng,Chen, Yongsheng,Liu, Qixing,Zhou, Haifeng
-
supporting information
(2020/10/14)
-
- Flow Microreactor Technology for Taming Highly Reactive Chloroiodomethyllithium Carbenoid: Direct and Chemoselective Synthesis of α-Chloroaldehydes
-
A straightforward flow synthesis of α-chloro aldehydes has been developed. The strategy involves, for the first time, the thermal unstable chloroiodomethyllithium carbenoid and carbonyl compounds. A batch versus flow comparative study showcases the superb capability of flow technology in prolonging the lifetime of the lithiated carbenoid, even at -20 °C. Remarkably, the high chemoselectivity realized in flow allowed for preparing polyfunctionalized α-chloro aldehydes not easily accessible with traditional batch procedures.
- Colella, Marco,Degennaro, Leonardo,Luisi, Renzo,Musci, Pantaleo,Romanazzi, Giuseppe,Sivo, Alessandra
-
p. 3623 - 3627
(2020/05/22)
-
- Palladium-Catalyzed Amide N-C Hiyama Cross-Coupling: Synthesis of Ketones
-
N-Acylglutarimides and arylsiloxanes reacted in the presence of Pd(OAc)2/PCy3, Et3N·3HF, and LiOAc to provide the corresponding arylketones in good yields. Aryl-, vinyl-, and alkyl-substituted N-acylglutarimides showed good activity in the coupling reactions of arylsiloxanes. The reaction had a broad substrate scope and showed good functional group tolerance. N-Benzoylsuccinimide and N-protected N-phenylbenzamides showed good activities in coupling reactions with phenylsiloxane. The employment of CuF2 as an activor afforded the decarbonylative products at 160 °C.
- Idris, Muhammad Aliyu,Lee, Sunwoo
-
supporting information
p. 9190 - 9195
(2020/11/18)
-
- Copper-Catalyzed Oxidative Fragmentation of Alkynes with NFSI Provides Aryl Ketones
-
A copper-catalyzed oxidative cleavage reaction of alkynes using NFSI and TBHP was described. Various terminal and internal alkyne substrates were employed to render quick access to aryl ketone products in moderate to good yields. NFSI not only functioned as N-centered radical precursors but also engaged in the aryl group migration. Mechanistic studies also suggested the important role of water in the title reactions.
- Chen, Hanfei,Cheng, Hao,Huang, Yifan,Jin, Chaochao,Song, Weihan,Tan, Chen,Tan, Jiajing,Tang, Lin,Yang, Fang,Zhang, Shuaifei
-
supporting information
(2020/11/03)
-
- Combined Photoredox/Enzymatic C?H Benzylic Hydroxylations
-
Chemical transformations that install heteroatoms into C?H bonds are of significant interest because they streamline the construction of value-added small molecules. Direct C?H oxyfunctionalization, or the one step conversion of a C?H bond to a C?O bond, could be a highly enabling transformation due to the prevalence of the resulting enantioenriched alcohols in pharmaceuticals and natural products,. Here we report a single-flask photoredox/enzymatic process for direct C?H hydroxylation that proceeds with broad reactivity, chemoselectivity and enantioselectivity. This unified strategy advances general photoredox and enzymatic catalysis synergy and enables chemoenzymatic processes for powerful and selective oxidative transformations.
- Betori, Rick C.,May, Catherine M.,Scheidt, Karl A.
-
p. 16490 - 16494
(2019/11/03)
-
- Chemoselective Synthesis of Aryl Ketones from Amides and Grignard Reagents via C(O)-N Bond Cleavage under Catalyst-Free Conditions
-
Conversion of a wide range of N-Boc amides to aryl ketones was achieved with Grignard reagents via chemoselective C(O)-N bond cleavage. The reactions proceeded under catalyst-free conditions with different aryl, alkyl, and alkynyl Grignard reagents. α-Ketoamide was successfully converted to aryl diketones, while α,β-unsaturated amide underwent 1,4-addition followed by C(O)-N bond cleavage to provide diaryl propiophenones. N-Boc amides displayed higher reactivity than Weinreb amides with Grignard reagents. A broad substrate scope, excellent yields, and quick conversion are important features of this methodology.
- Sureshbabu, Popuri,Azeez, Sadaf,Muniyappan, Nalluchamy,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
-
p. 11823 - 11838
(2019/10/02)
-
- Arylation of Aldehydes to Directly Form Ketones via Tandem Nickel Catalysis
-
A nickel-catalyzed arylation of both aliphatic and aromatic aldehydes proceeds with air-stable (hetero)arylboronic acids, with an exceptionally wide substrate scope. The neutral condition tolerates acidic hydrogen and sensitive polar groups and also preserves α-stereocenters of some chiral aldehydes. Interestingly, this nickel(0) catalysis does not follow common 1,2-insertion of arylmetal species to aldehydes and β-hydrogen elimination.
- Lei, Chuanhu,Zhu, Daoyong,Tangcueco, Vicente Iii Tiu,Zhou, Jianrong Steve
-
supporting information
p. 5817 - 5822
(2019/08/26)
-
- Continuous flow synthesis of diaryl ketones by coupling of aryl Grignard reagents with acyl chlorides under mild conditions in the ecofriendly solvent 2-methyltetrahydrofuran
-
An efficient continuous flow sequential synthesis of diaryl ketones was achieved by coupling of aryl Grignard reagents with acyl chlorides in the bio-derived “green” solvent 2-methyltetrahydrofuran (2-MeTHF) under mild reaction conditions (ambient temperature, 1 hour), allowing a safe and on-demand generation of 2-(3-benzoylphenyl)propionitrile with a productivity of 3.16 g hour?1
- Zhang, Chuan-Tao,Zhu, Rui,Wang, Zheng,Ma, Bing,Zajac, Adrian,Smiglak, Marcin,Xia, Chun-Nian,Castle, Steven L.,Wang, Wen-Long
-
p. 2199 - 2204
(2019/01/26)
-
- Palladium-Catalyzed Ligand-Free Decarboxylative Coupling of α- Oxocarboxylic Acid with Aryl Diazonium Tetrafluoroborate: An Access to Unsymmetrical Diaryl Ketones
-
Diaryl ketones are of much importance in organic synthesis as versatile intermediates and in industry for their useful properties. A mild and efficient palladium-catalyzed traditional ligand-free decarboxylative coupling of aryl α-keto carboxylic acid with aryl diazonium fluoroborate has been developed. A series of unsymmetrical diaryl ketones has been synthesized in moderate to good yields using this procedure. A radical pathway involving the acyl radical has been suggested.
- Panja, Subir,Maity, Pintu,Ranu, Brindaban C.
-
p. 12609 - 12618
(2018/10/20)
-
- Introducing Glycerol as a Sustainable Solvent to Organolithium Chemistry: Ultrafast Chemoselective Addition of Aryllithium Reagents to Nitriles under Air and at Ambient Temperature
-
Edging closer towards developing air and moisture compatible polar organometallic chemistry, the chemoselective and ultrafast addition of a range of aryllithium reagents to nitriles has been accomplished by using glycerol as a solvent, at ambient temperature in the presence of air, establishing a novel sustainable access to aromatic ketones. Addition reactions occur heterogeneously (“on glycerol conditions”), where the lack of solubility of the nitriles in glycerol and the ability of the latter to form strong intermolecular hydrogen bonds seem key to favouring nucleophilic addition over competitive hydrolysis. Remarkably, PhLi exhibits a greater resistance to hydrolysis working “on glycerol” conditions than “on water”. Introducing glycerol as a new solvent in organolithium chemistry unlocks a myriad of opportunities for developing more sustainable, air and moisture tolerant main-group-metal-mediated organic synthesis.
- Rodríguez-álvarez, María J.,García-álvarez, Joaquín,Uzelac, Marina,Fairley, Michael,O'Hara, Charles T.,Hevia, Eva
-
p. 1720 - 1725
(2018/01/27)
-
- Acyl and Decarbonylative Suzuki Coupling of N-Acetyl Amides: Electronic Tuning of Twisted, Acyclic Amides in Catalytic Carbon-Nitrogen Bond Cleavage
-
We report the Pd-catalyzed acyl and the Ni-catalyzed biaryl Suzuki-Miyaura cross-coupling of N-acetyl-amides with arylboronic acids by selective N-C(O) cleavage. Activation of the amide bond by N-acylation provides electronically destabilized, acyclic, nonplanar amide, which readily undergoes cross-coupling with a wide range of boronic acids to produce biaryl ketones or biaryls in a highly efficient manner. Most crucially, the presented results introduce N-acetyl-amides as reactive acyclic amides in the emerging manifold of transition-metal-catalyzed amide cross-coupling. The scope and origin of high selectivity are discussed. Mechanistic studies point to remodeling of amidic resonance and amide bond twist as selectivity determining features in a unified strategy for cross-coupling of acyclic amides. Structural studies, mechanistic investigations as well as beneficial effects of the N-acyl substitution on cross-coupling of amides are reported.
- Liu, Chengwei,Li, Guangchen,Shi, Shicheng,Meng, Guangrong,Lalancette, Roger,Szostak, Roman,Szostak, Michal
-
p. 9131 - 9139
(2018/09/21)
-
- Method of utilizing continuous flow microreactor to synthesize benzophenone derivative
-
The invention belongs to the technical field of organic synthesis, and particularly relates to a method of utilizing a continuous flow microreactor to synthesize a benzophenone derivative. The methodincludes: using aryl Grignard reagent and acyl chloride as raw materials; at normal temperature, continuously synthesizing the benzophenone derivative in the microreactor; recycling a reaction solvent2-methyl tetrahydrofuran. Problems of environmental pollution and reaction operation safety caused by the fact that conventional Fridel-Crafts reaction is excessively dependent on reagents like aluminum trichloride, ferric trichloride and zinc dichloride are avoided, the defect that novel catalytic processes are expensive in catalytic reagent and harsh in operation condition is made up, and continuous synthesis of a medical intermediate ketoprofen nitrile is realized efficiently. The method has the advantages of high operation convenience, high reaction safety, high yield, high efficiency andreaction solvent reusability and is environment-friendly and efficient.
- -
-
Paragraph 0041-0045
(2018/09/11)
-
- Co (II)-C12 alkyl carbon chain multi-functional ionic liquid immobilized on nano-SiO2 nano-SiO2@CoCl3-C12IL as an efficient cooperative catalyst for C–H activation by direct acylation of aryl halides with aldehydes
-
Nano-silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C-H activation. Catalytic results indicated that nano-SiO2 supported ionic liquid consisting C12 alkyl carbon chain and CoCl3 anion nano-SiO2@CoCl3-C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology.
- Hu, Yu Lin,Wu, Ya Pan,Lu, Ming
-
-
- Polystyrene-supported Pd(II)–N-heterocyclic carbene complex as a heterogeneous and recyclable precatalyst for cross-coupling of acyl chlorides with arylboronic acids
-
Palladium-catalysed cross-coupling reaction of aroyl chlorides with arylboronic acids was achieved in the presence of polystyrene-supported palladium(II)–N-heterocyclic carbene complex, using K2CO3 in acetone–water, providing diaryl ketones in high yields. Furthermore, the heterogeneous catalyst could be reused up to four times without significant loss of activity.
- Movassagh, Barahman,Hajizadeh, Fatemeh,Mohammadi, Elmira
-
-
- Pd-NHC catalysed Carbonylative Suzuki coupling reaction and its application towards the synthesis of biologically active 3-aroylquinolin-4 (1H)-one and acridone scaffolds
-
We have unfolded a convenient and mild protocol for the synthesis of diaryl ketones via Pd- NHC catalysed carbonylative Suzuki coupling reaction. Notably, this method offers advantages like no use of toxic CO gas, shorter reaction time, high yield, and broad substrate scope. Several sensitive functional groups (like-COMe, -COOMe, -F, -Cl, -Br, -NH2, -CN) are well tolerated in this reaction. In addition, we have also demonstrated a new efficient route for the synthesis of biologically active and pharmaceutically important 2-substituted 3-Aroylquinolin-4(1H)-ones and acridone scaffolds.
- Ghosh, Prasanjit,Ganguly, Bhaskar,Das, Sajal
-
-
- A simple, mild and efficient oxidation of benzylic alcohols in the presence of NBS/KOAc in aqueous solution
-
Background: The oxidation of benzylic alcohols to carbonyl compounds is a fundamental reaction in organic synthesis. In traditional oxidation processes, a large amount of toxic and volatile organic solvents and metal oxidants are used. Thus, developing environmentally benign oxidation processes is an important goal. N-Bromosuccinimide (NBS) is an inexpensive and convenient oxidant widely used in a variety of oxidative reactions under acidic or alkaline conditions. Methods: In this paper, we developed a simple, mild, and efficient oxidation of benzylic alcohols in the presence of N-bromosuccinimide (NBS)/KOAc in aqueous solution (H2O/CH2Cl2 = 3:1). Results: A series of benzylic alcohols were oxidized selectively to the corresponding ketones in moderate to excellent yields at room temperature. Conclusion: This reaction was carried out using a wide variety of substrates, required no metal catalyst, and proved to be tolerant towards a variety of different functional groups.
- Wu, Jianglong,Liu, Yan,Liu, Ping,Gu, Chengzhi
-
p. 254 - 260
(2017/07/15)
-
- Cu(II)-Catalyzed Ligand-Free Oxidation of Diarylmethanes and Second Alcohols in Water
-
We developed a simple and efficient Cu(II)-catalyzed ligand-free oxidation of diarylmethanes and secondary alcohols using 70% tert-butyl hydroperoxide (TBHP) in water. A series of diarylmethanes were directly oxidized into diaryl ketones in 67%–98% yields. Additionally, various secondary alcohols were also transformed into the desired products in 48%–98% yields. Importantly, the catalytic system in the absence of any organic solvent, surfactant, or phase transfer agent, had a wide substrate scope and a high tolerance for various functional groups.
- Wu, Jianglong,Liu, Yan,Ma, Xiaowei,Liu, Ping,Gu, Chengzhi,Dai, Bin
-
supporting information
p. 1391 - 139
(2017/09/30)
-
- N-Methylamino Pyrimidyl Amides (MAPA): Highly Reactive, Electronically-Activated Amides in Catalytic N-C(O) Cleavage
-
Despite recent progress in catalytic cross-coupling technologies, the direct activation of N-alkyl-N-aryl amides has been a challenging transformation. Here, we report the first Suzuki cross-coupling of N-methylamino pyrimidyl amides (MAPA) enabled by the controlled nN → πAr conjugation and the resulting remodeling of the partial double bond character of the amide bond. The new mode of amide activation is suitable for generating acyl-metal intermediates from unactivated primary and secondary amides.
- Meng, Guangrong,Lalancette, Roger,Szostak, Roman,Szostak, Michal
-
p. 4656 - 4659
(2017/09/12)
-
- Pd-PEPPSI: Pd-NHC Precatalyst for Suzuki-Miyaura Cross-Coupling Reactions of Amides
-
Pd-PEPPSI-IPr serves as a highly reactive precatalyst in the direct Suzuki-Miyaura cross-coupling of amides. An array of amides can be cross-coupled with a range of arylboronic acids in very good yields using a single, operationally simple protocol. The studies described represent the first use of versatile PEPPSI type of Pd-NHC complexes as catalysts for the cross-coupling of amides by N-C bond activation. The method is user-friendly, since it employs a commercially available, air- and moisture-stable Pd-PEPPSI-IPr complex. Pd-PEPPSI-IPr provides a significant improvement over all current Pd/phosphane catalysts for amide N-C bond activation. Mechanistic studies provide insight into the reaction rates of Pd-NHC-catalyzed cross-coupling of different amides, with Pd-PEPPSI-IPr being particularly effective for the cross-coupling of N-Boc carbamates under the developed conditions.
- Lei, Peng,Meng, Guangrong,Ling, Yun,An, Jie,Szostak, Michal
-
p. 6638 - 6646
(2017/07/15)
-
- General Method for the Suzuki-Miyaura Cross-Coupling of Amides Using Commercially Available, Air- and Moisture-Stable Palladium/NHC (NHC = N-Heterocyclic Carbene) Complexes
-
The direct Suzuki-Miyaura cross-coupling of amides catalyzed by Pd-NHC complexes is reported. Using a single protocol, commercially available, air- and moisture-stable (NHC)Pd(R-allyl)Cl complexes can effect Suzuki-Miyaura cross-coupling of a wide range of amides with arylboronic acids in very good yields. The studies described herein represent the use of versatile Pd-NHC complexes as catalysts for transition-metal-catalyzed cross-coupling of amides by N-C bond activation. The Pd-NHC catalysts provide a significant improvement over all current Pd-PR3 systems employed for the amide N-C bond activation. Mechanistic studies provide strong support for the development of a unified reactivity scale of the amide bond for the generation of acyl-metal intermediates.
- Lei, Peng,Meng, Guangrong,Szostak, Michal
-
p. 1960 - 1965
(2017/08/14)
-
- Palladium-Catalyzed Suzuki-Miyaura Cross-Coupling of N-Mesylamides by N-C Cleavage: Electronic Effect of the Mesyl Group
-
A general Pd-catalyzed Suzuki-Miyaura cross-coupling of N-mesylamides with arylboronic acids by selective N-C cleavage has been developed. The presented results represent the first example of a transition-metal-catalyzed cross-coupling of amides activated by an atom-economic, cheap, and benign mesyl group. The reaction delivers arylated products featuring a range of useful functional groups by chemoselective cleavage of the amide N-C bond with high efficiency. Both the scope and the origin of high selectivity are discussed. A beneficial effect of the N-mesyl substituent on the bond activation in acyclic amides is presented.
- Liu, Chengwei,Liu, Yongmei,Liu, Ruzhang,Lalancette, Roger,Szostak, Roman,Szostak, Michal
-
supporting information
p. 1434 - 1437
(2017/03/23)
-
- Palladium-Catalyzed Denitrogenative Synthesis of Aryl Ketones from Arylhydrazines and Nitriles Using O2 as Sole Oxidant
-
An efficient and simple palladium-catalyzed approach for the synthesis of aryl ketones from low-cost nitriles and arylhydrazines using molecular oxygen (O2) as sole oxidant via C-N bond cleavage is reported. Various aryl ketones were synthesized in moderate to good yields under mild conditions. A possible mechanism involving the PdII/Pd0 catalytic cycle process is depicted, and a cationic palladium intermediate was detected by ESI-MS.
- Wang, Xu,Huang, Yubing,Xu, Yanli,Tang, Xiaodong,Wu, Wanqing,Jiang, Huanfeng
-
p. 2211 - 2218
(2017/02/26)
-
- Palladium-catalyzed Suzuki-Miyaura coupling of amides by carbon-nitrogen cleavage: General strategy for amide N-C bond activation
-
The first palladium-catalyzed Suzuki-Miyaura cross-coupling of amides with boronic acids for the synthesis of ketones by sterically-controlled N-C bond activation is reported. The transformation is characterized by operational simplicity using bench-stable, commercial reagents and catalysts, and a broad substrate scope, including substrates with electron-donating and withdrawing groups on both coupling partners, steric-hindrance, heterocycles, halides, esters and ketones. The scope and limitations are presented in the synthesis of >60 functionalized ketones. Mechanistic studies provide insight into the catalytic cycle of the cross-coupling, including the first experimental evidence for Pd insertion into the amide N-C bond. The synthetic utility is showcased by a gram-scale cross-coupling and cross-coupling at room temperature. Most importantly, this process provides a blueprint for the development of a plethora of metal catalyzed reactions of typically inert amide bonds via acyl-metal intermediates. A unified strategy for amide bond activation to enable metal insertion into N-C amide bond is outlined (Scheme 1).
- Meng, Guangrong,Szostak, Michal
-
supporting information
p. 5690 - 5707
(2016/07/06)
-
- Palladium-Catalyzed suzuki?Miyaura cross-Coupling of amides via site-Selective n?C bond cleavage by cooperative catalysis
-
Palladium-catalyzed Suzuki?Miyaura cross-coupling of primary benzamides enabled by a merger of site-selective N,N-di-Boc-activation and cooperative catalysis via N?C bond cleavage for the synthesis of biaryl ketones is reported. We present the synergistic combination of Lewis base and palladium catalysis as a concept to activate inert amide N?C bonds. The mild reaction conditions provide a direct route to structurally diverse ketones. The reaction tolerates a wide range of electrophilic functional groups. Considering the fundamental importance of primary amides as pharmaceutical and synthetic intermediates, the strategy has a potential for developing a diverse array of valuable amide N?C bond functionalization reactions by the synergistic merger of Lewis base and organometallic catalysis.
- Meng, Guangrong,Shi, Shicheng,Szostak, Michal
-
p. 7335 - 7339
(2018/05/22)
-
- Synthesis of 2-fluorocholine aryl carbonyl compounds
-
The invention provides a method for synthesizing 2-fluoroarylcarbonyl compounds, which comprises the following steps: converting arylcarbonyl compounds into corresponding carbonyl oxime ether compounds, mildly implementing aryl hydrocarbon chain direct fluoridation of high-selectivity oximido substituent group ortho-position in the presence of a palladium catalyst, a fluoridation reagent and additives, and finally, rehydrolyzing oxime ethers under the action of acid to obtain the 2-fluoroarylcarbonyl compounds. The fluoridation method has the advantages of mild reaction conditions, high substrate adaptability, high fluoridation selectivity and the like, is simple to operate, and has higher application research value.
- -
-
Paragraph 0113; 0114; 0117
(2017/02/09)
-
- N-acylsaccharins: Stable electrophilic amide-based acyl transfer reagents in Pd-catalyzed Suzuki-Miyaura coupling via N-C cleavage
-
The development of efficient catalytic methods for N-C bond cleavage in amides remains an important synthetic challenge. The first Pd-catalyzed Suzuki-Miyaura cross-coupling of N-acylsaccharins with boronic acids by selective N-C bond activation is reported. The reaction enables preparation of a variety of functionalized diaryl and alkyl-aryl ketones with broad functional group tolerance and in good to excellent yields. Of general interest, N-acylsaccharins serve as new, highly reactive, bench-stable, economical, amide-based, electrophilic acyl transfer reagents via acyl-metal intermediates. Mechanistic studies strongly support the amide N-C(O) bond twist as the enabling feature of N-acylsaccharins in the N-C bond cleavage.
- Liu, Chengwei,Meng, Guangrong,Liu, Yongmei,Liu, Ruzhang,Lalancette, Roger,Szostak, Roman,Szostak, Michal
-
supporting information
p. 4194 - 4197
(2016/09/09)
-
- Multiwalled Carbon Nanotubes Supported Pd(II)-Salen Complex: An Effective, Phosphorous-Free, and Reusable Heterogeneous Precatalyst for the Synthesis of Diaryl Ketones
-
The Suzuki–Miyaura cross-coupling reaction of aroyl chlorides and arylboronic acids has been carried out efficiently in the presence of Pd(II)-salen@MWCNTs as an air-moisture stable precatalyst. The influence of various parameters, such as solvent, temperature, and base on the reaction system, was studied. Furthermore, the catalyst can be easily recovered quantitatively by a simple filtration and reused for three consecutive runs without significant loss of its activity.
- Mohammadi, Elmira,Hajilou, Zahra,Movassagh, Barahman
-
p. 747 - 752
(2016/09/20)
-
- Uncatalyzed CO2Li-Mediated SNAr Reaction of Unprotected Benzoic Acids via Silicon Trickery
-
The alkyl and aryllithium nucleophilic aromatic substitution (SNAr) displacement of a fluoro or methoxy group from unprotected 2-fluoro/methoxybenzoic acids is discussed. It was discovered that a TMS group located at the C6-position ortho to the carboxyl group shields effectively the carboxylate against nucleophilic attack, thus reducing dramatically ketone formation, and reorients nucleophilic substitution to the C2-position. The reactions with fluoro-substituted substrate 7 proceed efficiently; in contrast, the use of methoxy-functionalized benzoic acid 8 only affords moderate yields with s-BuLi and PhLi. This uncatalyzed coupling reaction, which provides a direct access to biaryl compounds, presumably proceeds by an addition-elimination sequence via intermediate formation of a resonance-stabilized pentavalent silalactone-Meisenheimer complex.
- Belaud-Rotureau, Mickael,Castanet, Anne-Sophie,Nguyen, Thi Huu,Mortier, Jacques
-
p. 307 - 313
(2016/03/30)
-
- Elemental step thermodynamics of various analogues of indazolium alkaloids to obtaining hydride in acetonitrile
-
A series of analogues of indazolium alkaloids were designed and synthesized. The thermodynamic driving forces of the 6 elemental steps for the analogues of indazolium alkaloids to obtain hydride in acetonitrile were determined using an isothermal titration calorimeter (ITC) and electrochemical methods, respectively. The effects of molecular structure and substituents on the thermodynamic driving forces of the 6 steps were examined. Meanwhile, the oxidation mechanism of NADH coenzyme by indazolium alkaloids was examined using the chemical mimic method. The result shows that the oxidation of NADH coenzyme by indazolium alkaloids in vivo takes place by one-step concerted hydride transfer mechanism.
- Lei, Nan-Ping,Fu, Yan-Hua,Zhu, Xiao-Qing
-
p. 11472 - 11485
(2015/12/04)
-
- Synthesis of structurally diverse diarylketones through the diarylmethyl sp3 C-H oxidation
-
Under open-flask conditions, an efficient method to assemble a series of diversely functionalized diarylketones in the presence of commercially available NBS has been developed. Yields of up to 99% have been achieved employing diarylmethanes as starting material. Based on 18O-labeled experiment, the addition of stoichiometric water eventually leads to excellent yields in all carbonylation cases.
- He, Chao,Zhang, Xiaohui,Huang, Ruofeng,Pan, Jing,Li, Jiaqiang,Ling, Xuege,Xiong, Yan,Zhu, Xiangming
-
p. 4458 - 4462
(2014/08/05)
-
- Acyl hydrazides as acyl donors for the synthesis of diaryl and aryl alkyl ketones
-
In this communication we describe a novel strategy for the formation of valuable diaryl and aryl alkyl ketones from acyl hydrazides. A wide variety of ketones are prepared and the mild reaction conditions allow for the use of a range of functionalities, especially in the synthesis of diaryl ketones.
- Akhbar, Ahmed R.,Chudasama, Vijay,Fitzmaurice, Richard J.,Powell, Lyn,Caddick, Stephen
-
p. 743 - 746
(2014/01/06)
-
- An efficient approach to deoximation using hexachlorodisilane under mild conditions
-
A simple, facile, and efficient procedure for deoximation of oximes to the corresponding ketones and aldehydes with hexachlorodisilane (Si2Cl6) in the presence of SiO2 from good to high yields is described. Apparently, SiO2 greatly increases the reaction rate and product yield. The proposed procedure is more advantageous than those described previously due to its higher efficiency, milder reaction conditions, shorter reaction, and easier work-up.
- Du, Liyong,Gao, Jing,Yang, Shuyang,Wang, Dawei,Han, Xinxin,Xu, Yongjian,Ding, Yuqiang
-
p. 2200 - 2204
(2015/02/02)
-
- Expedient carbonylation of aryl halides in aqueous or neat condition
-
An expedient and versatile, microwave-assisted procedure for the carbonylation of aryl halides with boronic acids, alcohols or amines in water or under neat conditions has been developed. The reaction is catalyzed by fluorous, oxime-based palladacycle 1 that shows an excellent recyclable property and low levels of Pd leaching. To demonstrate the usefulness of the protocol, we applied it to the preparation of compounds of pharmaceutical interest, including a precursor of the reverse transcriptase inhibitor, niacin, benzocaine and butamben.
- Ang, Wei Jie,Lo, Lee-Chiang,Lam, Yulin
-
p. 8545 - 8558
(2014/12/11)
-
- Pd-NHC-catalyzed synthesis of diaryl ketones
-
With N-hetereocyclic carbene and palladium catalysis, diaryl ketones with a variety of functional groups that span from electron withdrawing to electron donating substitutions can be conveniently synthesized using the corresponding aryl boronic acid and N-acyloxyphthalimide.
- Gao, Feng,Feng, Huangdi,Sun, Zhihua
-
p. 6451 - 6454
(2014/12/10)
-
- Direct electrosynthesis of ketones from benzylic methylenes by electrooxidative C-H activation
-
Electrify your chemistry! Direct electrosynthesis of ketones from benzylic methylenes in an undivided cell was realized in moderate to good yields (see scheme). In this electrosynthesis, electrons instead of conventional oxidants and catalysts are employed to make the reaction environmentally benign. Moreover, the reaction intermediate radical was detected by ESR spectroscopy and the reaction mechanism was clarified.
- Meng, Li,Su, Jihu,Zha, Zhenggen,Zhang, Li,Zhang, Zhenlei,Wang, Zhiyong
-
p. 5542 - 5545
(2013/05/23)
-
- DMC mediated one pot synthesis of biaryl ketones from aryl carboxylic and boronic acids
-
Synthesis of biaryl ketones has been realized from aryl carboxylic acids in the presence of DMC, facilitated by palladium catalyst under thermal condition. This methodology gives the introduction of carbonyl functionality in one pot from corresponding ary
- Pathak, Arunendra,Rajput, Chatrasal S.,Bora, Pushkar S.,Sharma, Somesh
-
p. 2149 - 2150
(2013/05/08)
-
- Steric and electronic effects influencing β-aryl elimination in the Pd-catalyzed carbon-carbon single bond activation of triarylmethanols
-
An analysis of the palladium-catalyzed activation of carbon-carbon single bonds within triarylmethanols has led to a greater understanding of factors influencing the β-aryl elimination process responsible for C-C bond cleavage. A series of competition reactions were utilized to determine that β-aryl elimination of aryl substituents containing ortho-substitution proceeds with significant preference to unsubstituted phenyl rings. Further experiments indicate that substrates containing either strongly donating or withdrawing substituents are cleaved from triarylmethanols more readily than relatively neutral species.
- Bour, James R.,Green, Jacob C.,Winton, Valerie J.,Johnson, Jeffrey B.
-
p. 1665 - 1669
(2013/03/28)
-