- Hydrogen bonding Part 44. 1-Methyl-1,3,5,7-tetra-aza-adamantan-1-ium (N-methylhexamethylenetetramine cation) halide hydrates: IR and thermodynamic study of planar C2h(H2O*Br-)2 and (H2O*Cl-)2 clusters, a possible C2h(H2O*I-)2 cluster,and two higher Cl- hydrates
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The IR spectrum of the C2h(H2O*Br-)2 cluster in the bromide monohydrate of the N-methylhexamethylenetetramine cation (MHMTA+) correlates well with that of the C2h(H2O*Cl-)2 cluster in the tetraethylammonium chloride monohydrate.MHMTA+Cl- forms a monohydrate which contains a similar cluster, as well as a dihydrate and trihydrate.Equilibrium dissociation vapor pressure measurements show that the minimum value for H-O-H...X- hydrogen bonds is about 6.5 kcal mol-1 in the bromide monohydrate and about 7.5 kcal mol-1 in the chloride monohydrate.MHMTA+I- forms an ephemeral monohydrate; dissociation measurements over a limited range suggest a minimum value of about 8 kcal mol-1 for H-O-H...I- hydrogen bonds.The IR spectrum of the iodide monohydrate does not distinguish clearly between a planar cyclic and an extended spiral structure for the water-iodide structure.
- Harmon, Kenneth M.,Keefer, Patricia K.
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- Preparation method of hexafluoropropylene dipolymer
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The invention discloses a preparation method of a hexafluoropropylene dipolymer. The method comprises the steps that preheated hexafluoropropylene gas is introduced into a reaction container filled with alkyl hexamethylenetetramine fluorine salts show as a formula (IV); continuous reaction is performed under the heating and stirring conditions; reaction products are treated to obtain the hexafluoropropylene dipolymer; in the formula (IV) shown in the description, R is an alkyl group with the carbon number being 1 to 10. The preparation method is used as a novel reaction route; the condition that catalysts and solvents are used for polymerization reaction in a traditional process is avoided; the preparation process is simple; the equipment requirements are low; the reaction conditions are mild.
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Paragraph 0018; 0019; 0020
(2018/11/22)
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- Energetic nitrate, perchlorate, azide and azolate salts of hexamethylenetetramine
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Hexamethylenetetrammonium salts, composed of energetic anions 3,5-dinitropyrazolate, 4,5-dinitroimidazolate, 3,5-dinitro-1,2,4-triazolate, 5-nitrotetrazolate, perchlorate, nitrate and azide, were synthesized and characterized. The structure of N-methyl-hexamethylenetetrammonium 3,5-dinitro-1,2,4-triazolate (6) was confirmed by X-ray analysis. The standard enthalpies of formation for the new salts were calculated by using the computationally feasible DFT(B3LYP) and MP2 methods in conjunction with an empirical approach based on the densities of the salts. The calculated values range from ΔHfo = -30.6 (7) to +468.8 kJ·mol-1 (10) where the experimental densities > 1.35 g cm-3. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Xue, Hong,Gao, Haixiang,Twamley, Brendan,Shreeve, Jean'ne M.
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p. 2959 - 2965
(2007/10/03)
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- Methylhexamethylenetetramine fluoride dihydrate: A new fluorodenitration reagent
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Methylhexamethylenetetramine fluoride dihydrate has been prepared by conventional methods. It is moderately soluble in polar aprotic solvents, and shows good thermal stability, enabling it to be dried. The reagent is capable of converting activated nitroaromatics to the corresponding fluoroaromatics, with a high selectivity to monofluorodenitration being observed with some polysubstituted aromatics.
- Clark, James H.,Nightingale, David J.
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