- Process for Productions of Formamides and Acrylamides
-
This invention relates to performance chemicals field, it discloses a novel and green process for simultaneous productions of formamides as well as mono- and multi-functional acrylamides under very mild conditions and with high efficiency. These substances are widely useful as industrial solvents or raw materials, in particular acrylamides are important olefinically-unsaturated polymerizable monomers in photo-curing materials.
- -
-
Paragraph 0022; 0023
(2020/02/27)
-
- In situ generated amine as a Lewis base catalyst in the reaction of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3.3.1]nonane in nitric acid: Experimental and DFT study
-
The problem how ammonium nitrate affects the nitrolysis of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3.3.1]nonane (DPT) in nitric acid to prepare 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) has puzzled chemists for decades. In this paper, experimental work and theoretical calculation are described to investigate the long-standing challenge. The experiment results showed that ammonium nitrate or alkylammonium chlorides were in favor of the formation of 1-nitroso-3,5,7-trinitro-1,3,5,7-tetraazacyclooctane (MNX) but hindered the conversion of MNX to HMX. A plausible catalytic mechanism was proposed. In which ammonia or amines, in situ generated from the unfavorable balance with their salts, act as Lewis base catalysts. At the same time, the DFT computation results reveal that rigid bicyclic transition states established with 1-hydroxymethyl-3,5,7-trinitro-1,3,5,7-tetraazacyclooctane, ammonia (or amines) and three water molecules lead to very low activation energies. Then, a novel process for the preparation of MNX with excellent yield up to 78.5% was developed, which is free of the use of NaNO2 or N2O4 as nitroso resources.
- Zhang, Yu,Chi, Guoli,He, Ying,Xu, Zishuai,Zhang, Luyao,Luo, Jun,Zhou, Baojing
-
supporting information
(2019/04/08)
-
- A simple method for the preparation of propargylamines using molecular sieve modified with copper(II)
-
A new, heterogeneous, 4 A molecular sieve-supported copper(ii) catalyst was developed and was used successfully in the A3 coupling of alkynes, aldehydes and amines under simple reaction conditions.
- Fodor, Anna,Kiss, Arpad,Debreczeni, Nora,Hell, Zoltan,Gresits, Ivan
-
scheme or table
p. 4575 - 4581
(2010/11/19)
-
- Tocopherols by hydride reduction of dialkylamino derivatives
-
Aminomethylation with Mannich reagents derived from secondary amines and paraformaldehyde under improved conditions has been used to convert non-α-tocopherol homologues into α-tocopherol, the biologically most important vitamin E compound. Mono- and bis(aminomethylated) β-, γ-and δ-tocopherol were then subsequently transformed into the corresponding tocopherols (α- and β-tocopherol) by reductive deamination. As an alternative to classical catalytic hydrogenation in the last step, efficient laboratory protocols using complex hydrides have been derived and applied to the preparation of labelled vitamin E compounds. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Netscher, Thomas,Mazzini, Francesco,Jestin, Roselyne
-
p. 1176 - 1183
(2008/02/08)
-
- Aminomethylation of tocopherols
-
A process for the production of a Mannich reagent comprises reacting formaldehyde, especially paraformaldehyde, with a secondary amine in the complete or almost complete absence of a solvent. An alternative comprises reacting a diaminomethane produced from a secondary amine, formaldehyde, especially paraformaldehyde, as well as water with one another in about equimolar amounts. The invention is also concerned with a process for the aminomethylation of δ-tocopherol or of tocopherol mixtures containing this and comprises using a Mannich reagent which has been produced in the above manner. After completion of this aminomethylation process excess Mannich reagent can be separated by distillation and can be reacted with water and formaldehyde, especially paraformaldehyde, in order to regenerate further Mannich reagent suitable for use in the aminomethylation, this regeneration representing a further aspect of the invention. Finally, the invention includes certain novel bis(aminomethyl)-γ-tocopherols.
- -
-
-
- Nitrite Ion as a Nitrosating Reagent. Nitrosation of Morpholine and Diethylamine in the Presence of Formaldehyde
-
The kinetics of the nitrosation of morpholine and diethylamine in the presence of formaldehyde has been studied at pH values between 6.5-8.2 and 6.9-8.7, respectively.The results are interpreted through a mechanism that implies the reaction between both the nitrite NO2(-) and iminium R2N(+)=CH2 ions.The latter ion results from the dehydration of the conjugated acid of the carbinolamine, R2NH(+)CH2OH, the initial product of the amine-formaldehyde reaction.The results allow the calculation of the equlibrium constants of the formation of carbinolamine, R2NCH2OH, and methanediamine, R2NCH2NR2 (only for the morpholine-formaldehyde system), and their conjugate acids.
- Casado, Julia,Mosquera, Manuel,Paz, L. Carlos,Prieto, M. Flor Rodriguez,Tato, Jose Vazquez
-
p. 1963 - 1966
(2007/10/02)
-