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G. Kumaraswamy A. Pitchaiah G. Ramakrishna D.S. Ramakrishna K. Sadaiah 《Tetrahedron letters》2006,47(12):2013-2015
An efficient protocol for the benzylation or allylation of amides using the corresponding benzyl or allyl chlorides as electrophiles under basic conditions with commercially available 5 mol % of [Cu(OH)TMEDA]2Cl2 as catalyst was developed. Under these conditions, unprotected amino acids were benzylated without any racemization. 相似文献
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Qi Lin You-Ming Zhang Li-Ming Gao Tai-Bao Wei Hai Wang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2051-2057
A novel and efficient method for synthesis ethoxycarbonyl isothiocyanate and ethoxycarbonyl thioureas catalyzed by TMEDA is reported. A series of N-aryl-N′-ethoxycarbonyl thioureas and arene (or polymethylene)-bis-ethoxycarbonyl thiourea derivatives have been synthesized in good-to-excellent yields via this method at room temperature. 相似文献
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Gareth J. Rowlands Author Vitae 《Tetrahedron》2010,66(9):1593-501
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Abdullahi Mustapha Krystoff Busch Marta Patykiewicz Alistair Apedaile John Reglinski Alan R. Kennedy Timothy J. Prior 《Polyhedron》2008
The reaction of the Schiff base species tris-((2-hydroxybenzylidene)aminoethyl)-amine (TrenSal) and tris-((2-hydroxy-5-bromobenzylidene)aminoethyl)amine (Tren5BrSal) with the acetates of nickel and zinc are reported. Two trimetallic complexes (M3L2) of Tren5BrSal with nickel and zinc have been crystallographically characterised. The attempted crystallisation of bis-(tris-((2-hydroxybenzylidene)aminoethyl)amine nickel) nickel from solutions containing TMEDA lead to the production of two novel complexes: namely a nickel adduct of the partially hydrolysed TrenSal ligand and an interesting nickel bromide–carbonate salt. [(TrenSal)2Ni3] is reacted with PbCl2 to form a novel tetrametallic complex, [{(TrenSal)Ni}Pb(NC5H5)Cl]2, where a Pb2Cl2 moiety replaces the nickel at the core of the complex. Extending the study to include the related hexadentate ligand, 1,1,1-tris-((2-hydroxybenzylidene)-aminomethyl)propane (TEtSal), we were able to isolate and characterise both [(TEtSal)2Ni3] and [{(TEtSal)Ni}2Pb]. 相似文献
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Crystal Structures of TMEDA Adducts and of Salts with Protonated TMEDA Molecules The reaction of TMEDA with two equivalents of [BH3(SMe2)] in toluene at 20 °C gives the adduct [TMEDA(BH3)2] ( 1 ). A similar reaction of pyrrolidine with [BH3(SMe2)] in a molar ratio of 1:1 leads to the adduct [pyrrolidine(BH3)] ( 2 ). TMEDA can be introduced into the coordination sphere of In3+ by the treatment of InI3 with TMEDA in toluene to give the complex [InI(TMEDA)] ( 3 ). The salt [HTMEDA]I ( 4 ), containing a mono‐protonated TMEDA molecule, is the result of the reprotonation of [NH4]I and TMEDA in toluene at 20 °C. The salts [H2TMEDA]—[InCl4(TMEDA)]2 ( 5 ) and [H2TMEDA][InCl5(THF)] ( 6 ) are formed in the reaction mixtures TMEDA/toluene/InCl3/HCl and TMEDA/toluene/THF/InCl3/HCl, respectively, whereupon 6 was characterized more closely. Crystals of [In5I6(OH)(TMEDA)4]I·2, 5toluene ( 7 ·2.5toluene) can be obtained after treatment of InI3 with non‐dried TMEDA; 4 was identifed as by‐product. 1 — 7 ·2.5toluene were partially investigated by NMR methods and vibrational spectroscopy. In all cases a characterization by single crystal X‐ray diffraction was performed. According to this, all nitrogen atoms in 1 and 2 are coordinated by BH3 groups leading to a distorted tetrahedral environment at the nitrogen and the boron atoms. In 3 a distorted trigonal‐bipyramidal coordination sphere at the In3+ is present. The apical positions are occupied by I3 and N3. Strong N‐H···N bridges, running along [001] is the feature in 4 ; the I—‐Ions are not involved into the system of H‐bridges. A ion triple, [H2TMEDA][InCl4(TMEDA)]2, hold together by bifurcated H‐bridges is the dominating structural motif in 5 , whereas alternation bifurcated and linear H‐bridges, leading zu a zig‐zag chain along [100], is the build‐up principle of 6 . In 7 ·2.5toluene a complex In5O8 skeleton was formed, consisting of a virtual corner‐connected doubled heterocubane. At every heterocubane a corner, occupied by a metal ion, is missing. The coordination spheres of the In atoms of the complex cation are completed by TMEDA molecules and iodide ions. 相似文献
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Dr. Peter G. N. Neate Dr. Mark D. Greenhalgh Dr. William W. Brennessel Dr. Stephen P. Thomas Prof. Dr. Michael L. Neidig 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(39):17218-17224
N,N,N′,N′-Tetramethylethylenediamine (TMEDA) has been one of the most prevalent and successful additives used in iron catalysis, finding application in reactions as diverse as cross-coupling, C−H activation, and borylation. However, the role that TMEDA plays in these reactions remains largely undefined. Herein, studying the iron-catalyzed hydromagnesiation of styrene derivatives using TMEDA has provided molecular-level insight into the role of TMEDA in achieving effective catalysis. The key is the initial formation of TMEDA–iron(II)–alkyl species which undergo a controlled reduction to selectively form catalytically active styrene-stabilized iron(0)–alkyl complexes. While TMEDA is not bound to the catalytically active species, these active iron(0) complexes cannot be accessed in the absence of TMEDA. This mode of action, allowing for controlled reduction and access to iron(0) species, represents a new paradigm for the role of this important reaction additive in iron catalysis. 相似文献
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