- Copper-Catalyzed Radical N-Demethylation of Amides Using N-Fluorobenzenesulfonimide as an Oxidant
-
An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.
- Yi, Xuewen,Yi, Xuewen,Lei, Siyu,Liu, Wangsheng,Che, Fengrui,Yu, Chunzheng,Liu, Xuesong,Wang, Zonghua,Zhou, Xin,Zhang, Yuexia
-
supporting information
p. 4583 - 4587
(2020/05/05)
-
- N-Heterocyclic Carbene/Cobalt Cooperative Catalysis for the Chemo- and Regioselective C?N Bond Formation between Aldehyde and Amines/Amides
-
A novel methodology for the construction of various secondary (4 examples), tertiary amides (31 examples), and imides (16 examples) by a Cobalt(II) catalyzed oxidative amide coupling in aqueous media. The Co(III)-TMC was reacted with N-Heteroatom Carbene to form active catalyst Co(II)NHC-TMC in situ which involves in the coordination with Breslow's intermediate and SET for the activation of aldehyde and amides. The mechanism for activation of amide and amine differs on the basis of SET based nucleophilic addition and ligand exchange respectively. The regeneration of the catalyst was achieved using Fe(III)(EDTA)-H2O2 as oxidant. The use of Co(II)TMC-O2 was also found equally efficient in the process. The method is found regioselective for N?H activation in the presence of equally susceptible ortho-C?H bond activation. And amines were found more susceptible then the corresponding amide for the reaction.
- Siddiqui, Asher M.,Khalid, Anam,Khan, Arif,Azad, Chandra S.,Samim, Mohd.,Khan, Imran A.
-
p. 4281 - 4287
(2020/07/24)
-
- An efficient synthesis of benzothiazole using tetrabromomethane as a halogen bond donor catalyst
-
An efficient and mild protocol has been developed for the synthesis of 2-substituted benzothiazole under solvent- and metal-free conditions using CBr4 as the catalyst. This process involves the activation of a thioamide through halogen bond formation between the sulphur atom of the thioamide and bromine atom of the CBr4 molecule. The presence of halogen-bonding interaction between N-methylthioamides and tetrabromomethane has been demonstrated with several control experiments, spectroscopic analysis and density functional theory (DFT). This methodology has a wide substrate scope for the synthesis of both 2-alkyl and 2-aryl substituted benzothiazoles.
- Kazi, Imran,Sekar, Govindasamy
-
p. 9743 - 9756
(2019/12/02)
-
- Utilizing Carbonyl Coordination of Native Amides for Palladium-Catalyzed C(sp3)?H Olefination
-
PdII-catalyzed C(sp3)?H olefination of weakly coordinating native amides is reported. Three major drawbacks of previous C(sp3)?H olefination protocols, 1) in situ cyclization of products, 2) incompatibility with α-H-containing substrates, and 3) installation of exogenous directing groups, are addressed by harnessing the carbonyl coordination ability of amides to direct C(sp3)?H activation. The method enables direct C(sp3)?H functionalization of a wide range of native amide substrates, including secondary, tertiary, and cyclic amides, for the first time. The utility of this process is demonstrated by diverse transformations of the olefination products.
- Park, Hojoon,Li, Yang,Yu, Jin-Quan
-
supporting information
p. 11424 - 11428
(2019/07/17)
-
- Acyl-Directed ortho-Borylation of Anilines and C7 Borylation of Indoles using just BBr3
-
Indoles are privileged heterocycles found in many biologically active pharmaceuticals and natural products. However, the selective functionalization of the benzenoid moiety in indoles in preference to the more reactive pyrrolic unit is a significant challenge. Herein we report that N-acyl directing groups enable the C7-selective C?H borylation of indoles using just BBr3. This transformation shows some functional-group tolerance and notably proceeds with C6 substituted indoles. The directing group can be readily removed in situ and the products isolated as the pinacol boronate esters. Acyl-directed electrophilic borylation can be extended to carbazoles and anilines with excellent ortho selectivity. 4-amino-indoles are amenable to this process, with acyl group installation and directed electrophilic C?H borylation enabling selective formation of C5-BPin-indoles.
- Iqbal, Saqib A.,Cid, Jessica,Procter, Richard J.,Uzelac, Marina,Yuan, Kang,Ingleson, Michael J.
-
supporting information
p. 15381 - 15385
(2019/10/22)
-
- Nickel-catalyzed C-N bond reduction of aromatic and benzylic quaternary ammonium triflates
-
A nickel-catalyzed, efficient C-N bond reduction of aromatic and benzylic ammonium triflates has been developed using sodium isopropoxide as a reducing agent. The high efficiency, mild conditions, and good compatibility with various substituents made this method an effective supplement to the current catalytic hydrogenation reactions. Combining this reductive deamination reaction with directed aromatic functionalization reactions, a powerful strategy for regioselective functionalization of arenes was demonstrated using dialkylamine groups as traceless directing groups.
- Yi, Yuan-Qiu-Qiang,Yang, Wen-Cheng,Zhai, Dan-Dan,Zhang, Xiang-Yu,Li, Shuai-Qi,Guan, Bing-Tao
-
supporting information
p. 10894 - 10897
(2016/09/09)
-
- α-Arylation of Saturated Azacycles and N-Methylamines via Palladium(II)-Catalyzed C(sp3)-H Coupling
-
Pd(II)-catalyzed α-C(sp3)-H arylation of pyrrolidines, piperidines, azepanes, and N-methylamines with arylboronic acids has been developed for the first time. This transformation is applicable to wide arrays of pyrrolidines and boronic acids, including heteroaromatic boronic acids. A diastereoselective one-pot heterodiarylation of pyrrolidines has also been achieved.
- Spangler, Jillian E.,Kobayashi, Yoshihisa,Verma, Pritha,Wang, Dong-Hui,Yu, Jin-Quan
-
supporting information
p. 11876 - 11879
(2015/10/05)
-
- Competitive reaction pathways for o-Anilide aryl radicals: 1,5-Or 1,6-hydrogen transfer versus nucleophilic coupling reactions. A novel rearrangement to afford an amidyl Radical
-
The photoinduced reactions of o-iodoanilides (o-IC6H 4N(Me)COR, 4a-d) with sulfur nucleophiles such as thiourea anion (1, -SCNH(NH2)), thioacetate anion (2, MeCOS-), and sulfide anion (3,S2-/sup
- Rey, Valentina,Pierini, Adriana B.,Penenory, Alicia B.
-
body text
p. 1223 - 1230
(2009/07/04)
-
- Deacylation of esters, thioesters and amides by a naphthalene-catalysed lithiation
-
The reaction of different esters, thioesters and amides derived from pivalic, benzoic and 4-tert-butylbenzoic acids with an excess of lithium and a catalytic amount of naphthalene (8 mol%) led, after methanolysis, to the corresponding alcohols, thiols and amines, respectively, through a reductive non-hydrolytic procedure. This methodology represents a reasonable alternative to other non-reductive protocols. Georg Thieme Verlag Stuttgart.
- Behloul, Cherif,Guijarro, David,Yus, Miguel
-
p. 309 - 314
(2007/10/03)
-
- Polymer-supported mukaiyama reagent: A useful coupling reagent for the synthesis of esters and amides
-
(Chemical equation presented) Polymer-supported N-alkyl-2-chloro pyridinium triflate was synthesized in one step from Wang resin. This reagent proved to be a very effective coupling reagent for the synthesis of esters or amides from carboxylic acids and alcohols or amines (primary and secondary).
- Crosignani, Stefano,Gonzalez, Jerome,Swinnen, Dominique
-
p. 4579 - 4582
(2007/10/03)
-
- Carbanionically Induced -Migrations of ?- and Coordinatively Unsaturated Groups
-
According to a general reaction scheme, o-lithioaryl esters 4a,b, amides 13a,b 17b, and amidines 39b of non-enolizable carboxylic acids as well as a corresponding diphenylphosphinic amide 51b react under mild conditions to give the intensely coloured lithium derivatives of o-acylphenoles 6a,b and o-acylarenamines 15a,b, 18a, 41a, 52a, which are finally hydrolyzed to the neutral products 7a,b, 14a,b, 18b, 41b, 52b, respectively.The lithiated precursors of the rearrangement are mostly prepared by halogen/metal exchange reactions.In the case of N,N-di-p-tolylpivalamide 33 such a -rearrangement also could be induced by direct metalation of the educt.With N-methyl-N-phenylpivalamide (29), however, exclusive metalation of the N-methyl group occurs, followed by -migration of the pivaloyl group.Silyl groups, too, can undergo analogous -shifts, as was demonstrated by the rearrangement of the o-lithiated N-(trimethylsilyl)aniline 63b to the o-(trimethylsilyl)anilines 65a,b.When a benzoyl and sulfonyl group can compete for the -shifts, as in the N-tosylated benzamide 47b, only the benzoyl group migrates.However, the migration tendency of the trimethylsilyl group equals that of the benzoyl group as was shown with the N-silylated benzamide 66b.
- Hellwinkel, Dieter,Laemmerzahl, Frank,Hofmann, Gunter
-
p. 3375 - 3405
(2007/10/02)
-
- 10. Nucleophile Aminoalkylierung mit Thiopivalamiden
-
Of the twelwe thioamides 7a-e and 8a-g, only N,N-dimethylthiopivalamide (7a) could be metallated at the CH-group in α-position to the N-atom.The reagent 9 thus obtained (Table 1) reacts in high yields with primary haloalkanes, with aldehydes, and with non-enolizable ketones (Table 2).As shown in Scheme 1, the products can be hydrolyzed to pivalamides, cleaved to secondary amines, or reduced to neopentylamines (see 18/19, 15/equation (4) and (5), and 16/20, respectively).
- Lubosch, Winfried,Seebach, Dieter
-
p. 102 - 116
(2007/10/02)
-