154150-18-2Relevant articles and documents
N-boc protection of amines with di-tert-butyldicarbonate in water under neutral conditions in the presence of β-cyclodextrin
Somi Reddy,Narender,Nageswar,Rama Rao
, p. 1110 - 1112 (2006)
A new protocol for protection of aryl and aliphatic amines was developed with (Boc)2O in the presence of β-cyclodextrin in water. A catalytic amount of β-cyclodextrin is specific for activation of amines. This procedure works well on a wide variety of both electron-rich and electron-deficient amines. Georg Thieme Verlag Stuttgart.
Thiamine hydrochloride as a recyclable organocatalyst for the efficient and chemoselective N-tert-butyloxycarbonylation of amines
Ingale, Ajit P.,Garad, Dnyaneshwar N.,Ukale, Dattatraya,Thorat, Nitin M.,Shinde, Sandeep V.
supporting information, p. 3791 - 3804 (2021/11/04)
Thiamin hydrochloride promoted highly efficient and ecofriendly approach has been described for the chemoselective N-tert-butyloxycarbonylation of amines under solvent-free conditions at ambient temperature. The demonstrated approach has been applicable for the N-Boc protection of variety of aliphatic, aryl, heteroaryl amines. The chemoselective protection of amino group occurs in chiral amines and amino alcohol without racemization in high yield. Thiamin hydrochloride is stable, economical, easy to handle and environmentally friendly.
Bis(4-benzhydryl-benzoxazol-2-yl)methane – from a Bulky NacNac Alternative to a Trianion in Alkali Metal Complexes
Kretsch, Johannes,Kreyenschmidt, Anne-Kathrin,Schillm?ller, Timo,L?kov, M?rt,Herbst-Irmer, Regine,Leito, Ivo,Stalke, Dietmar
supporting information, p. 9858 - 9865 (2021/05/29)
A novel sterically demanding bis(4-benzhydryl-benzoxazol-2-yl)methane ligand 6 (4?BzhH2BoxCH2) was gained in a straightforward six-step synthesis. Starting from this ligand monomeric [M(4-BzhH2BoxCH)] (M=Na (7), K (81)) and dimeric [{M(4-BzhH2BoxCH)}2] (M=K (82), Rb (9), Cs (10)) alkali metal complexes were synthesised by deprotonation. Abstraction of the potassium ion of 8 by reaction with 18-crown-6 resulted in the solvent separated ion pair [{(THF)2K@(18-crown-6)}{bis(4-benzhydryl-benzoxazol-2-yl)methanide}] (11), including the energetically favoured monoanionic (E,E)-(4-BzhH2BoxCH) ligand. Further reaction of 4?BzhH2BoxCH2 with three equivalents KH and two equivalents 18-crown-6 yielded polymeric [{(THF)2K@(18-crown-6)}{K@(18-crown-6)K(4-BzhBoxCH)}]n (n→∞) (12) containing a trianionic ligand. The neutral ligand and herein reported alkali complexes were characterised by single X-ray analyses identifying the latter as a promising precursor for low-valent main group complexes.
Pendant Alkoxy Groups on N-Aryl Substitutions Drive the Efficiency of Imidazolylidene Catalysts for Homoenolate Annulation from Enal and Aldehyde
Kyan, Ryuji,Mase, Nobuyuki,Narumi, Tetsuo,Sato, Kohei
supporting information, p. 19031 - 19036 (2020/08/25)
Hydrogen-transfer in the tetrahedral intermediate generated from an imidazolylidene catalyst and α,β-unsaturated aldehyde forms a conjugated Breslow intermediate. This is a critical step affecting the efficiency of the NHC-catalyzed γ-butyrolactone formation via homoenolate addition to aryl aldehydes. A novel type of imidazolylidene catalyst with pendant alkoxy groups on the ortho-N-aryl groups is described. Catalyst of this sort facilitates the formation of the conjugated Breslow intermediate. Studies of the rate constants for homoenolate annulation affording γ-butyrolactones, reveal that introduction of the oxygen atoms in the appropriate position of the N-aryl substituents can increase the efficiency of imidazolylidene catalysts. Structural and mechanistic studies revealed that pendant alkoxy groups can be located close to the proton of the tetrahedral intermediate, thereby facilitating the proton transfer.
Highly efficient chemoselective N-tert butoxycarbonylation of aliphatic/aromatic/heterocyclic amines using diphenylglycoluril as organocatalyst
Awasthi, Amardeep,Mukherjee, Anagh,Singh, Mandeep,Rathee, Garima,Vanka, Kumar,Chandra, Ramesh
, (2020/05/14)
An efficient approach for the Chemoselective N-tert-butoxycarbonylation of a variety of amines using diphenylglycoluril as organocatalyst has been described. For the first time, a plausible mechanism for the N-tert-butoxycarbonylation has been proposed using density functional theory (DFT) calculations supported by NMR studies. The reusability of the organocatalyst and observation of the desired N-Boc protected amines being formed without the formation of side products like urea, oxazolidinone, isocyanate, and N, N-di-Boc derivatives makes the present protocol desirable.
PRIMIN DERIVATIVES, METHOD OF PREPARATION THEREOF AND USE THEREOF
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Page/Page column 4, (2017/03/28)
The present invention provides primin derivatives of general formula II and/or III, wherein R1 is selected from the group consisting of methyl and hydrogen, R2 is selected from the group consisting of methoxy, hydroxy, hydrogen, Rsu
Palladium-Catalyzed Decarboxylative Synthesis of Arylamines
Dai, Qipu,Li, Peihe,Ma, Nuannuan,Hu, Changwen
, p. 5560 - 5563 (2016/11/17)
A novel approach has been developed for the synthesis of arylamines via the palladium-catalyzed intramolecular decarboxylative coupling (IDC) of aroyloxycarbamates, obtained in situ by reacting aryl carboxylic acids with hydroxycarbamates. The reaction offers facile access to structurally diverse arylamines with the site-specific formation of the C(sp2)-N bond under mild conditions.
The cooperative FeCl3/DDQ system for the regioselective synthesis of 3-arylindoles from β-monosubstituted 2-alkenylanilines
Jang, Su San,Youn, So Won
supporting information, p. 2200 - 2204 (2016/03/01)
A highly regioselective synthesis of 3-arylindoles by using the cooperative FeCl3/DDQ system has been developed. This new protocol represents an attractive route for the synthesis of 3-arylindoles from readily accessible non-indole precursors, β-aryl-substituted 2-styrylanilines, using an inexpensive catalyst and oxidant. Noteworthy is the unique synergetic and synergistic effect of FeCl3 and DDQ on the 1,2-aryl migratory process.
Ligand-Promoted Meta-C-H Arylation of Anilines, Phenols, and Heterocycles
Wang, Peng,Farmer, Marcus E.,Huo, Xing,Jain, Pankaj,Shen, Peng-Xiang,Ishoey, Mette,Bradner, James E.,Wisniewski, Steven R.,Eastgate, Martin D.,Yu, Jin-Quan
supporting information, p. 9269 - 9276 (2016/08/05)
Here we report the development of a versatile 3-acetylamino-2-hydroxypyridine class of ligands that promote meta-C-H arylation of anilines, heterocyclic aromatic amines, phenols, and 2-benzyl heterocycles using norbornene as a transient mediator. More than 120 examples are presented, demonstrating this ligand scaffold enables a wide substrate and coupling partner scope. Meta-C-H arylation with heterocyclic aryl iodides as coupling partners is also realized for the first time using this ligand. The utility for this transformation for drug discovery is showcased by allowing the meta-C-H arylation of a lenalidomide derivative. The first steps toward a silver-free protocol for this reaction are also demonstrated.
Installation of protected ammonia equivalents onto aromatic & heteroaromatic rings in water enabled by micellar catalysis
Isley, Nicholas A.,Dobarco, Sebastian,Lipshutz, Bruce H.
supporting information, p. 1480 - 1488 (2014/03/21)
A single set of conditions consisting of a palladium catalyst, a commercially available ligand, and a base, allow for several types of C-N bond constructions to be conducted in water with the aid of a commercially available "designer" surfactant (TPGS-750-M). Products containing a protected NH2 group in the form of a carbamate, sulfonamide, or urea can be fashioned starting with aryl or heteroaryl bromides, iodides, and in some cases, chlorides, as substrates. Reaction temperatures are in the range of room temperature to, at most, 50 °C, and result in essentially full conversion and good isolated yields.
