1740-57-4Relevant articles and documents
Extended structures controlled by intramolecular and intermolecular hydrogen bonding: A case study with pyridine-2,6-dicarboxamide, 1,3-benzenedicarboxamide and N,N'-dimethyl-2,6-pyridinedicarboxamide
Marlin,Olmstead,Mascharak
, p. 211 - 223 (2000)
The small organic molecule pyridine-2,6-dicarboxamide, although known in the literature for some time, exhibits interesting and previously unexplored intermolecular and intramolecular hydrogen bonding both in solid state and in solution. With the aid of X-ray crystallography and variable-temperature NMR spectroscopy, we here demonstrate the presence of a very strong hydrogen bonding network for this molecule both in condensed state and solution. Furthermore, a novel extended hydrogen bonding graph-set has been derived for this molecule in crystalline state. Comparison of pyridine-2,6-dicarboxamide with 1,3-benzenedicarboxamide, where the intramolecular hydrogen bonding to the pyridine ring in the former has been removed, yields a different intermolecular hydrogen bonded structure in the solid state. A new graph-set has been determined for the extended structure of 1,3-benzenedicarboxamide in the solid state. In solution, 1,3-benzenedicarboxamide is shown to maintain a hydrogen bonding pattern that is weaker than that observed with pyridine-2,6-dicarboxamide. Replacement of one hydrogen on each carboxamide nitrogen of pyridine-2,6-dicarboxamide by a methyl group also alters the extended structure to a significant extent. In N,N'-dimethyl-2,6-pyridinedicarboxamide, the three-dimensional hydrogen bonding pattern observed with pyridine-2,6-dicarboxamide all but collapses to one-dimensional chains. (C) 2000 Elsevier Science B.V.
Preparation method of M-phenylenediamine
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Paragraph 0006; 0016; 0017; 0019; 0020; 0022; 0023; 0025, (2021/02/10)
The invention belongs to the technical field of petrochemical organic synthesis, and particularly relates to a preparation method of m-phenylenediamine. According to the invention, m-phthalonitrile isused as a reaction raw material, and m-phenylenediamine is prepared through two steps of reactions of catalytic hydrolysis amidation and Hofmann degradation. According to the method, the key technical problems that in the process of producing m-phenylenediamine through benzene nitration and hydrogenation in a traditional process, due to the fact that dangerous processes of nitration and hydrogenation are involved, potential safety hazards in the production process are large, and the environment is polluted are solved, nitration and hydrogenation reactions are not involved in the process, thereaction temperature is low, reaction is mild, control is easy, the yield reaches 80% or above, and product purity reaches 95% or above.
Preparation of m-phenylenediamine by using Huffman rearrangement method
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Paragraph 0070-0072, (2020/08/02)
The invention relates to the field of organic functional new material chemicals, and discloses a new process technology for preparing m-phenylenediamine from isophthalamide or a precursor compound thereof through a Huffman rearrangement method for the first time. The m-phenylenediamine is bulk key fine chemicals which are widely used in the related fields such as known dyes and pigments, medical pesticides, building auxiliary materials and the like, and the production process innovation technology of the m-phenylenediamine is widely concerned.