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1.
S.V. Kini 《Tetrahedron letters》2004,45(21):4171-4173
Hofmann degradation of 1-arylmethyl-1,2,3,4-tetrahydro-2,2-dimethylisoquinolinium iodides with methanolic KOH gave stilbene derivatives, for example, (E)-N-2{2-[2-(phenyl)ethenyl]-4,5-dimethoxyphenyl}ethyl-N,N-dimethylamine. Photochemical electrocyclization of these stilbenes afforded the corresponding phenanthrene alkaloids/phenanthrene derivatives.  相似文献   
2.
Infrared spectra of Mn(NH3)2Zn(CN)4.2C6H6 andMn(ethylenediamine)Zn(CN)4.2C6H6 are reported. The spectral data suggest that these compounds are similar in structure toHofmann-Td-type and the en-Td-type clathrates,respectively. There is good evidence for H-bonding from ammoniaN–H to benzene as a to H-bond.  相似文献   
3.
A novel method for the synthesis of chiral α-amino acids has been developed where the acid functionality was constructed by oxidizing a hydroxymethyl group introduced by Evans’ method in the α-position of an appropriate acid substrate and the amino part came from the amide of the original carboxyl group following a modified Hofmann rearrangement reaction.  相似文献   
4.
Azetidinium triflates were reacted in a one-pot two-steps sequence involving, generation of an azetidinium ylide, its alkylation with an halide, and final regioselective Hofmann elimination of the produced alkylated azetidinium ion to yield substituted α,β-unsaturated nitriles bearing an aminoethyl side-chain. The scope of this sequence was examined, and was found to depend both on the steric hindrance around the reactive center in the starting azetidinium salt, and on the nature of the reacting halide. Produced acrylonitriles were further used in DBU-catalyzed conjugate addition of amines, to yield 4-amino-2-aminomethyl-butyronitriles with fair diastereoselectivity, or, alternatively, to give C2 symmetrical cyclopropanes.  相似文献   
5.
A novel route to synthesize crosslinked porous polyvinylamine (PVAm) microspheres from acrylonitrile (AN) was developed. In the first step, crosslinked porous polyacrylonitrile (PAN) spheres were prepared by copolymerization of AN and divinylbenzene (DVB). Then they were hydrolyzed to form polyacrylamide (PAM) spheres. And lastly, the porous PVAm spheres were successfully obtained via Hofmann degradation of PAM spheres. Scanning electron microscope (SEM) indicated that these PVAm microspheres have rough surfaces and porous interior structure. The pore size, the amino content, and the content of equilibrium water were also investigated. The pore size of these PVAm microspheres increased with the hydrolytic process. The contents of equilibrium water was changed from 49.6 to 96.5% depending on the different crosslinking degrees, and the amino contents were varied between 9.60 and 15.30 mmol/g depending on the different molar ratio of n(NaClO)/n(NaOH). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1674–1682, 2008  相似文献   
6.
The paper consists of two parts. In the first part, we prove a noncommutative analog of the Riesz(— Markov—Kakutani) theorem on representation of functionals on an algebra of continuous functions by regular measures on the underlying space. In the second part, using this result, we prove a weak version of a Burnside type theorem on twisted conjugacy for arbitrary discrete groups.  相似文献   
7.
Two protocols for the efficient transformation of aromatic as well as aliphatic primary carboxamides to the corresponding carbamates and aromatic as well as aliphatic cyclic imides to the corresponding anthranilic acid derivatives & amino acid derivatives, respectively, are described. We also developed a novel methodology to the multigram scale synthesis of gabapentin and (S)-pregabalin. The gabapentin methyl carbamate was converted to novel potential peptide prodrugs of gabapentin.  相似文献   
8.
Spin-crossover complexes with multistep transitions attract much attention due to their potential applications as multi-switches and for data storage. A four-step spin crossover is observed in the new iron(II)-based cyanometallic guest-free framework compound Fe(2-ethoxypyrazine)2{Ag(CN)2}2 during the transition from the low-spin to the high-spin state. A reverse process occurs in three steps. Crystallographic studies reveal an associated stepwise evolution of the crystal structures. Multiple transitions in the reported complex originate from distinct FeII sites which exist due to the packing of the ligand with a bulky substituent.  相似文献   
9.
The nitrogen-rich compounds and intermediates with structure of monocyclic, bicyclic, and fused rings based on 1,2,3-triazole were synthesized and prepared by using a promising precursor named 4,5-dicyano-1,2,3-triazole, which was obtained by the cyclization reaction of diaminomaleonitrile. Their structure and configurational integrity were assessed by Fourier transform-infrared spectroscopy (FT-IR), mass spectrometry (MS), and elemental analysis (EA). Additionally, fourteen compounds were further confirmed by X-ray single crystal diffraction. Meanwhile, the physical properties of four selected compounds (3·H2O, 6·H2O, 10·H2O, and 16) including thermal stability, detonation parameters, and sensitivity were also estimated. All these compounds could be considered to construct more abundant 1,2,3-triazole-based neutral energetic molecules, salts, and complex compounds, which need to continue study in the future in the field of energetic materials.  相似文献   
10.
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