- A case study of Pd?Pd intramolecular interaction in a benzothiazole based palladacycle; catalytic activity toward amide synthesisviaan isocyanide insertion pathway
-
An acetate bridge benzothiazolepalladacycle containing a rare metallophilic intramolecular Pd?Pd interaction was synthesized and thoroughly characterized. The synthesized benzothiazolepalladacycle directly anchored on SBA-15 to form an efficient heterogen
- Loni, Masood,Balmohammadi, Yaser,Dadgar Yeganeh, Reza,Imani, Kaveh,Notash, Behrouz,Bazgir, Ayoob
-
supporting information
p. 3290 - 3297
(2021/02/26)
-
- Metal-free Photocatalytic Intermolecular anti-Markovnikov Hydroamination of Unactivated Alkenes
-
The development of photocatalytic intermolecular hydroamination reaction between N-aminated dihydropyridines and unactivated alkenes is reported. Metal-free co-catalysts, rhodamine 6G and thiophenol, in presence of visible light are used to initiate the process. The transformation shows a broad substrate scope, both alkenes and amidyl radical can act as coupling partners. The radical strategy provides excellent anti-Markovnikov selectivity and regioselectivity in diene substrates.
- Li, Juncheng,Wang, Ting,Zhao, Gaoyuan
-
supporting information
p. 2650 - 2654
(2021/06/25)
-
- Copper(II)-Photocatalyzed N-H Alkylation with Alkanes
-
We report a practical method for the alkylation of N-H bonds with alkanes using a photoinduced copper(II) peroxide catalytic system. Upon light irradiation, the peroxide serves as a hydrogen atom transfer reagent to activate stable C(sp3)-H bonds for the reaction with a broad range of nitrogen nucleophiles. The method enables the chemoselective alkylation of amides and is utilized for the late-stage functionalization of N-H bond containing pharmaceuticals with good to excellent yields. The mechanism of the reaction was preliminarily investigated by radical trapping experiments and spectroscopic methods.
- Donabauer, Karsten,K?nig, Burkhard,Narobe, Rok,Yakubov, Shahboz,Zheng, Yi-Wen
-
p. 8582 - 8589
(2020/09/23)
-
- Nickel-Catalyzed Reductive Addition of Aryl/Benzyl Halides and Pseudohalides to Carbodiimides for the Synthesis of Amides
-
A Nickel-catalyzed reductive process is described for the direct amidation of benzyl and aryl halides using carbodiimides as the amidating agent. Moreover, aryl and benzyl C–O electrophiles such as triflate, acetate, tosylate, trityl ether, and pivalate were converted into amides using this method. The in-situ-generated Ni0acts as a catalyst for the reaction at room temperature for benzylic substrates, and 70 °C for aryl electrophiles. This new nickel-catalyzed reductive coupling protocol provides a general and operationally simple method for the synthesis of diverse amides using carbodiimides. Amides bearing bulky substituents can be synthesized by this strategy in high yield, which demonstrates its effectiveness in amide synthesis.
- Panahi, Farhad,Jamedi, Fereshteh,Iranpoor, Nasser
-
p. 780 - 788
(2017/01/18)
-
- Amidation via ligand-free direct oxidative C(sp3)-H/N[sbnd]H coupling with Cu-CPO-27 metal-organic framework as a recyclable heterogeneous catalyst
-
A copper-based metal-organic framework Cu-CPO-27 was synthesized, and used as a recyclable catalyst for the amidation of unactivated alkanes by benzamides via direct oxidative C(sp3)-H/N[sbnd]H coupling under ligand-free conditions. Using a catalytic amount of the Cu-CPO-27 for the transformation, high yields of N-cyclohexyl benzamides were achieved. The Cu-CPO-27 was more catalytically active than other Cu-MOFs such as Cu3(BTC)2, Cu(BDC), Cu(EDB), Cu2(BPDC)2(BPY), Cu2(BDC)2(DABCO), and Cu2(EDB)2(BPY). The Cu-CPO-27 also exhibited advantages as compared to several copper-based salts, including Cu(OAc)2, CuCl2, CuBr, CuI, CuCl, Cu(NO3)2, and CuSO4. The Cu-CPO-27 catalyst could be reused several times for the amidation transformation while its catalytic activity was not decreased significantly. To the best of our knowledge, the amidation of unactivated alkanes by benzamides via direct oxidative C(sp3)-H/N[sbnd]H coupling was not previously performed under heterogeneous catalysis conditions.
- Hoang, Thanh T.,Nguyen, Hanh T.H.,Le, Tien T.,Le, Dung T.,Truong, Thanh,Phan, Nam T.S.
-
p. 8241 - 8251
(2016/11/23)
-
- Copper-catalyzed oxidative C(sp3)-H/N-H coupling of sulfoximines and amides with simple alkanes via a radical process
-
A copper-catalyzed oxidative C(sp3)-H/N-H coupling of sulfoximines with simple alkanes was developed. This protocol involved C(sp3)-N bond formation via a radical pathway and tolerated a series of functional groups, such as chloro, m
- Teng, Fan,Sun, Song,Jiang, Yan,Yu, Jin-Tao,Cheng, Jiang
-
supporting information
p. 5902 - 5905
(2015/03/30)
-
- Synthesis of amides via copper-catalyzed amidation of aryl halides using isocyanides
-
An efficient method for intermolecular CC cross-coupling reactions between isocyanides and aryl halides, catalyzed by copper(I) oxide, is developed. This transformation serves as a direct method for the preparation of benzamides in aqueous DMSO, in moderate to good yields.
- Yavari, Issa,Ghazanfarpour-Darjani, Majid,Bayat, Mohammad J.
-
p. 4981 - 4982
(2015/01/09)
-
- Copper-catalyzed intermolecular amidation and imidation of unactivated alkanes
-
We report a set of rare copper-catalyzed reactions of alkanes with simple amides, sulfonamides, and imides (i.e., benzamides, tosylamides, carbamates, and phthalimide) to form the corresponding N-alkyl products. The reactions lead to functionalization at secondary C-H bonds over tertiary C-H bonds and even occur at primary C-H bonds. [(phen)Cu(phth)] (1-phth) and [(phen)Cu(phth)2] (1-phth2), which are potential intermediates in the reaction, have been isolated and fully characterized. The stoichiometric reactions of 1-phth and 1-phth2 with alkanes, alkyl radicals, and radical probes were investigated to elucidate the mechanism of the amidation. The catalytic and stoichiometric reactions require both copper and tBuOOtBu for the generation of N-alkyl product. Neither 1-phth nor 1-phth2 reacted with excess cyclohexane at 100 C without tBuOOtBu. However, the reactions of 1-phth and 1-phth2 with tBuOOtBu afforded N-cyclohexylphthalimide (Cy-phth), N-methylphthalimide, and tert-butoxycyclohexane (Cy-OtBu) in approximate ratios of 70:20:30, respectively. Reactions with radical traps support the intermediacy of a tert-butoxy radical, which forms an alkyl radical intermediate. The intermediacy of an alkyl radical was evidenced by the catalytic reaction of cyclohexane with benzamide in the presence of CBr4, which formed exclusively bromocyclohexane. Furthermore, stoichiometric reactions of [(phen)Cu(phth)2] with tBuOOtBu and (Ph(Me)2CO) 2 at 100 C without cyclohexane afforded N-methylphthalimide (Me-phth) from β-Me scission of the alkoxy radicals to form a methyl radical. Separate reactions of cyclohexane and d12-cyclohexane with benzamide showed that the turnover-limiting step in the catalytic reaction is the C-H cleavage of cyclohexane by a tert-butoxy radical. These mechanistic data imply that the tert-butoxy radical reacts with the C-H bonds of alkanes, and the subsequent alkyl radical combines with 1-phth2 to form the corresponding N-alkyl imide product.
- Tran, Ba L.,Li, Bijie,Driess, Matthias,Hartwig, John F.
-
supporting information
p. 2555 - 2563
(2014/03/21)
-
- Pd(ii)-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates under mild conditions
-
A novel Pd-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates has been realized under mild reaction conditions. This method provides an efficient access to N-mono- or N,N-disubstituted benzamides and benzoates.
- Li, Mingzong,Wang, Cong,Fang, Ping,Ge, Haibo
-
supporting information; experimental part
p. 6587 - 6589
(2011/06/25)
-