Search results for "Nitromethane"
showing 10 items of 66 documents
Di-chlorido-[N-(N,N-di-methyl-carbamimido-yl)-N',N',4-tri-methyl-benzohydrazonamide]-platinum(II) nitro-methane hemisolvate.
2014
In the title compound, [PtCl2(C13H21N5)]·0.5CH3NO2, the PtIIatom is coordinated in a slightly distorted square-planar geometry by two Cl atoms and two N atoms of the bidentate ligand. The (1,3,5-triazapentadiene)PtIImetalla ring is slightly bent and does not conjugate with the aromatic ring. In the crystal, N—H...Cl hydrogen bonds link the complex molecules, forming chains along [001]. The nitromethane solvent molecule shows half-occupancy and is disordered over two sets of sites about an inversion centre.
Solid-state NMR and computational investigation of solvent molecule arrangement and dynamics in isostructural solvates of droperidol.
2015
(13)C, (15)N and (2)H solid-state NMR spectroscopy have been used to rationalize arrangement and dynamics of solvent molecules in a set of isostructural solvates of droperidol. The solvent molecules are determined to be dynamically disordered in the methanol and ethanol solvates, while they are ordered in the acetonitrile and nitromethane solvates. (2)H NMR spectra of deuterium-labelled samples allowed the characterization of the solvent molecule dynamics in the alcohol solvates and the non-stoichiometric hydrate. The likely motion of the alcohol molecules is rapid libration within a site, plus occasional exchange into an equivalent site related by the inversion symmetry, while the water mo…
CCDC 781923: Experimental Crystal Structure Determination
2011
Related Article: K.Helttunen, E.Nauha, A.Kurronen, P.Shahgaldian, M.Nissinen|2011|Org.Biomol.Chem.|9|906|doi:10.1039/c0ob00602e
A catalytic highly enantioselective direct synthesis of 2-bromo-2-nitroalkan-1-ols through a Henry reaction.
2008
Highly enantiomerically enriched 2-bromo-2-nitroalkan-1-ols are prepared by direct condensation of aliphatic and aromatic aldehydes with bromonitromethane in the presence of a catalytic amount of copper(II) acetate and a C1-symmetric camphorderived amino pyridine ligand. Blay Llinares, Gonzalo, Gonzalo.Blay@uv.es ; Hernandez Olmos, Victor, Victor.Hernandez@uv.es ; Pedro Llinares, Jose Ramon, Jose.R.Pedro@uv.es
Modular iminopyridine ligands. Application to the enantioselective copper(II)-catalyzed Henry reaction
2006
Abstract Chiral iminopyridines prepared in a modular fashion from monoterpenic (camphor-derived) ketones and pyridinylalkylamines catalyze the enantioselective Henry (nitro aldol) reaction between nitromethane and o -anisol in the presence of copper(II) acetate, with high yields and good ee (up to 86%) under straightforward experimental conditions without the need for air or moisture exclusion.
Enantioselective Henry reaction catalyzed with copper(II)–iminopyridine complexes
2007
Abstract Copper complexes of chiral iminopyridines prepared from camphane-derived ketones and picolylamine catalyzed the enantioselective Henry (nitroaldol) reaction between nitromethane and a number of aromatic and aliphatic aldehydes with high yields and good enantioselectivities. Iminopyridines derived from (1 R )-(+)-camphor and (1 S )-(+)-ketopinic acid gave the best results to afford the opposite enantiomers in each case, despite the fact they have the same stereochemical pattern at the camphane skeleton. The reactions were carried out without air or moisture exclusion.
New highly asymmetric Henry reaction catalyzed by Cu(II) and a C(1)-symmetric aminopyridine ligand, and its application to the synthesis of miconazol…
2008
A new catalytic asymmetric Henry reaction has been developed that uses a C(1)-symmetric chiral aminopyridine ligand derived from camphor and picolylamine. A variety of aromatic, heteroaromatic, aliphatic, and unsaturated aldehydes react with nitromethane and other nitroalkanes in the presence of DIPEA (1.0 equiv), Cu(OAc)(2)*H(2)O (5 mol %), and an aminopyridine ligand (5 mol %) to give the expected products in high yields (up to 99 %), moderate-to-good diastereoselectivites (up to 82:18), and excellent enantioselectivities (up to 98 %). The reaction is air-tolerant and has been used in the synthesis of the antifungal agent miconazole.
Enantioselective Addition of Nitromethane to 2-Acylpyridine N-Oxides. Expanding the Generation of Quaternary Stereocenters with the Henry Reaction
2014
[EN] The direct asymmetric Henry reaction with prochiral ketones, leading to tertiary nitroaldols, is an elusive reaction so far limited to a reduced number of reactive substrates such as trifluoromethyl ketones or alpha-keto carbonyl compounds. Expanding the scope of this important reaction, the direct asymmetric addition of nitromethane to 2-acylpyridine N-oxides catalyzed by a BOX-Cu(II) complex to give the corresponding pyridine-derived tertiary nitroaldols having a quaternary stereogenic center with variable yields and good enantioselectivity, is described.
Addition of Nucleophiles to Fluorinated Michael Acceptors
2016
A series of nucleophiles, including primary and secondary amines, primary alcohols, and thiols, as well as diethyl malonate and nitromethane, were added to different fluorinated Michael acceptors including 2-fluoroalk-1-en-3-ones and 2-fluoro-1-phenylprop-2-en-1-one. The resulting beta-substituted afluoro ketones were isolated in 34-92 % yield, depending on the substrate and the nucleophile. The best yields were obtained with secondary amines and with p-methylthiophenol.
Multiconfigurational second-order perturbation study of the decomposition of the radical anion of nitromethane
2004
The doublet potential energy surfaces involved in the decomposition of the nitromethane radical anion (CH(3)NO(2) (-)) have been studied by using the multistate extension of the multiconfigurational second-order perturbation method (MS-CASPT2) in conjunction with large atomic natural orbital-type basis sets. A very low energy barrier is found for the decomposition reaction: CH(3)NO(2) (-)--[CH(3)NO(2)](-)--CH(3)+NO(2) (-). No evidence has been obtained on the existence of an isomerization channel leading to the initial formation of the methylnitrite anion (CH(3)ONO(-)) which, in a subsequent reaction, would yield nitric oxide (NO). In contrast, it is suggested that NO is formed through the …