18931-78-7Relevant academic research and scientific papers
Solvent-Free and Liquid-Phase Iodination of Thiophene Derivatives with Potassium Dichloroiodate Monohydrate
Hussain, Anwar,Sarkar, Akash Mamon,Sereda, Grigoriy,Zefirov, Nikolai
, p. 1140 - 1146 (2020/04/01)
Iodination of a series of benzene and thiophene derivatives by potassium dichloroiodate monohydrate was studied with and without a solvent. The liquid substrates tend to be more reactive in water while the solid substrates afford better yields in dichloromethane or under the solvent-free conditions. The 2-substituted thiophenes show good to excellent yields whereas the yield for 3-substituted and 3,4- or 2,4-disubstituted thiophenes and benzene derivatives are significantly lower. The mechanochemical reaction of 5-carbaldehyde-2,2′-bithiophene shows excellent yields, while 2,2′-bithiophene gives practical yields only in dichloromethane. In the case of thiophene and N -acetyl- p -toluidine, electrophilic iodination is accompanied by a small extent of chlorination.
Aromatic Halogenation Using N-Halosuccinimide and PhSSiMe3 or PhSSPh
Hirose, Yuuka,Yamazaki, Mirai,Nogata, Misa,Nakamura, Akira,Maegawa, Tomohiro
, p. 7405 - 7410 (2019/06/14)
We developed a mild aromatic halogenation reaction using a combination of N-halosuccinimide and PhSSiMe3 or PhSSPh. Less reactive aromatic compounds, such as methyl 4-methoxybenzoate, were brominated with PhSSiMe3 or PhSSPh and N-bromosuccinimide in high yields. No reaction was observed in the absence of PhSSiMe3 or PhSSPh. This method is also applicable to chlorination reactions using N-chlorosuccinimide and PhSSPh.
A Visible Light-Mediated Regioselective Halogenation of Anilides and Quinolines by Using a Heterogeneous Cu-MnO Catalyst
Singh, Harshvardhan,Sen, Chiranjit,Sahoo, Tapan,Ghosh, Subhash Chandra
, p. 4748 - 4753 (2018/09/06)
A simple and practical heterogeneous Cu-MnO catalyzed regioselective halogenation of anilides and quinolines under irradiation with household 40 W incandescent lamp was developed. This method uses a recyclable Cu-MnO catalyst, acetonitrile as an industrially friendly solvent, and economic N-halo succinimides as a halogenating source. The reaction is scalable and well tolerated with a broad range of functional groups.
Palladium-catalyzed ortho-halogenations of acetanilides with N-halosuccinimides via direct sp2 C–H bond activation in ball mills
Liu, Zi,Xu, Hui,Wang, Guan-Wu
supporting information, p. 430 - 435 (2018/02/27)
A solvent-free palladium-catalyzed ortho-iodination of acetanilides using N-iodosuccinimide as the iodine source has been developed under ball-milling conditions. This present method avoids the use of hazardous organic solvents, high reaction temperature,
Cobalt(II)-catalyzed regioselective C-H halogenation of anilides
Li, Ze-lin,Sun, Kang-kang,Cai, Chun
supporting information, p. 5433 - 5440 (2018/08/12)
A cobalt-catalyzed regioselective C-H halogenation methodology is reported herein. The highlight of this work is the highly selective C-H functionalization of anilides, which results in high-yielding, versatile, and practical halogenated products. Thereby, brominations, chlorinations and iodinations of many electron-rich and electron-deficient anilides were achieved in a highly selective fashion. Mechanistic studies with respect to the pathway of the reaction are also described.
Monoprotected l-Amino Acid (l-MPAA), Accelerated Bromination, Chlorination, and Iodination of C(sp2)?H Bonds by Iridium(III) Catalysis
Kathiravan, Subban,Nicholls, Ian A.
supporting information, p. 7031 - 7036 (2017/05/29)
Halogenated arenes are important structural motifs commonly found in biologically active molecules and used for a variety of transformations in organic synthesis. Herein, we report the mono-protected l-amino acid (l-MPAA) accelerated iridium(III)-catalyzed halogenation of (hetero)anilides at room temperature. This reaction constitutes the first example of an iridium(III)/l-MPAA-catalyzed general halogenation of (hetero)arenes through C(sp2)?H activation. Furthermore, we demonstrate the potential utility of our method through its use in the synthesis of a quinolone derivative.
Direct C-H substitution reaction of anilides using hypervalent iodine and their regioselective issues
Yamamoto, Kohki,Kamino, Shinichiro,Sawada, Daisuke
supporting information, p. 3936 - 3938 (2017/09/21)
The direct C-H substitution reactions of anilides using hypervalent iodine proceeded to afford azide, chloro, bromo, and fluoro derivatives, and their regioselectivity were described. In the specific reaction conditions, the unique regioisomers were obtai
Synthesis of 2-methylbenzoxazoles directly from: N -phenylacetamides catalyzed by palladium acetate
Wang, Biying,Jiang, Chengfei,Qian, Jiasheng,Zhang, Shuwei,Jia, Xiaodong,Yuan, Yu
, p. 101 - 107 (2017/12/27)
A method to synthesize 2-methylbenzoxazoles directly from N-phenylacetamides catalyzed by Pd(OAc)2 in the presence of K2S2O8 and TfOH has been developed. The desired products were obtained in moderate to excellent yields. This approach provides a facile procedure to prepare benzoxazoles with available substrates. It is found that TfOH is the key factor for this cyclization reaction. A plausible mechanism of the reaction is proposed according to the control reactions and the literature.
Mechanistic insight into the thermal 1,3-chlorine migrations of N-chloroacetanilides under neutral conditions
Cheng, Baoxiang,Xu, Jiaxi
, p. 518 - 525 (2017/05/01)
The mechanistic insight of the thermal 1,3-chlorine migration reactions of N-chloroacetanilides under neutral conditions has been investigated. The results indicate that the 1,3-chorinemigration reaction is initiated by the radical reaction of the homocleavage of the Cl-N bond and subsequent radical combination of the Cl-C bond on the aromatic rings. The radical mechanism was verified by the thermal rearrangement of Nchloro- N-(4-methylphenyl)acetamide in cumene. After generation of hydrochloric acid in the radical mechanism, the migrations occurred through the acid-catalyzed rearrangement as well as the acid-catalyzed Orton reaction. The current results provide a comprehensive understanding on the mechanistic insights in the Orton reaction under different conditions.
Mild C - H halogenation of anilides and the isolation of an unusual palladium(I)-palladium(II) species
Bedford, Robin B.,Haddow, Mairi F.,Mitchell, Charlotte J.,Webster, Ruth L.
supporting information; experimental part, p. 5524 - 5527 (2011/07/31)
Reducing the load: A facile palladium-catalyzed ortho-selective bromination and chlorination of anilides occurs under aerobic conditions at room temperature when N-halosuccinimides (NXS) are used in the presence of p-toluenesulfonic acid (PTSA). The orthopalladated PTSA complex is not only catalytically competent but also undergoes a reductive process to yield an unusual PdI-PdII tetramer (see structure; Pdgreen, Ored, Syellow, Cgray). Copyright
