نتایج جستجو برای: diamines
تعداد نتایج: 2106 فیلتر نتایج به سال:
This paper reports the synthesis of the first bis(amino)borate ligand, [Ph(2)B(CH(2)NMe(2))(2)](-), an anionic equivalent of tertiary diamines. Anionic [Ph(2)B(CH(2)NMe(2))(2)] is an excellent bidentate ligand auxiliary and is used to prepare a series of N-chelated, zwitterionic rhodium(I) complexes.
An efficient iodine-mediated oxidative annulation of aryl acetylenes-arylethenes-aromatic ketones with 1,2-diamines for the synthesis of pyrazines and regioselective synthesis of quinoxalines is presented. A multipathway coupled domino approach has been developed for the one-pot synthesis of 1,4-diazines with high functional group compatibility.
For the first time, a clear and unambiguous rationalization of chirality induction, inversion and subsequent amplification process has been demonstrated for the 1 : 1 sandwich and 2 : 3 host-guest supramolecular complexes consisting of Zn(II) host and chiral diamines as guests that has so far remained the most outstanding issue for the chirogenic process.
Visible-light-mediated photoredox-catalyzed aldimine-aniline and aldehyde-aniline couplings have been realized. The reductive single electron transfer (SET) umpolung of various carbonyl derivatives enabled the generation of intermediary ketyl and α-amino radical anions, which were utilized for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols.
Polyurethanes and polyurethane-ureas were prepared by the reaction of diethylene glycol and polyethylene glycol with excess of aromatic and aliphatic diisocyanate to yield isocyanate terminated prepolymers which were subsequently reacted with diols and diamines. These polymers were characterized by IR, 1HNMR spectra, viscosity measurements and thermogravimetric analysis.
A Michael addition reaction of cyclic ketones and piperidones to a vinyl phosphonate is described. The reaction, catalyzed by chiral diamines, produced geminal γ-oxobisphosphonates in high yields (up to 92%) and very high ees (up to >99%). Disubstituted ketones gave drs of up to 8 : 92. The synthesis and characterization of several new compounds with potential biological activity is described.
A catalytic asymmetric nitro-Mannich (aza-Henry) reaction with rare earth metal/alkali metal heterobimetallic catalysts is described. A Yb/K heterobimetallic catalyst assembled by an amide-based ligand promoted the asymmetric nitro-Mannich reaction to afford enantioenriched anti-b-nitroamines in up to 86% ee. Facile reduction of the nitro functionality allowed for efficient access to optically ...
Some new macrocyclic dibenzotetraoxadiamides, tribenzotetraoxadimides, tribenzopentaoxadiamide, tribenzohexaoxadiamide, and tetrabenzoheptaoxadiamide 15-22 have been prepared. These compounds were obtained in the macrocyclization step by reacting the diamines 6 and 7 with appropriate dicarboxylic acid dichlorides 8-14. The cyclization does not require high dilution techniques or template ef...
2,2'-disubstitutedamino-4-4'-bis-pyrimidines (3a-m) have been prepared by linking 2,4-dichloro-6-methyl-5-nitropyrimidine (1) with several diamines and subsequent reaction with suitable amines. some of these compounds (3c and 3j) which were reduced catalitically, on treatment with nitrous acid, urea in pyridine, and boiling thionyl chloride gave the corresponding bistriazolopyrimidin ...
Acyclic diamines are valuable feedstocks for polyamide synthesis. Ruthenium-alkylidene catalysed cross metathesis of amino alkenes is problematic and acyl derivatisation can result in less efficient syntheses, poor catalyst turnover and isomerisation. Temporary amine masking via stable and soluble ammonium salts delivers cyclic and acyclic aminoalkenes in high yield and purity.
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