1193-24-4Relevant articles and documents
Sustainable and cost-efficient electro-synthesis of formamidine acetate from cyanamide in aqueous acidic electrolyte
Güthner, Thomas,Klein, Martin,Sans, Jürgen,Thalhammer, Franz,Waldvogel, Siegfried R.
, p. 3289 - 3294 (2021)
Formamidine represents a versatile building block in synthetic organic chemistry. We developed a new electrochemical synthesis of formamidine acetate by cathodic reduction of cyanamide in an aqueous electrolyte and in high yield. The crude product could be used for further conversions, such as to pyrimidines without purification. Compared to established synthetic routes neither prior processing of cyanamide was necessary, nor precious transition-metal catalyst were required, nor any reagent waste was produced, and only biocompatible and sustainable solvents were employed for this process, following the requirements ofgreen chemistry.
Photochemical transformation of azoxystrobin in aqueous solutions
Boudina,Emmelin,Baaliouamer,Paisse,Chovelon
, p. 1280 - 1288 (2007)
The photochemical behaviour of azoxystrobin fungicide (AZX) in water was studied under laboratory conditions. Photodegradation was initiated using a solar simulator (xenon arc lamp) or a jacketed Pyrex reaction cell equipped with a 125 W, high-pressure mercury lamp. HPLC/MS analysis (APCI and ESI in positive and negative modes) was used to identify AZX photoproducts. The calculated polychromatic quantum efficiencies (φ{symbol}) of AZX at pH 4.5, 7 and 9 were 5.42 × 10-3, 3.47 × 10-3 and 3.06 × 10-3 (degraded molecules per absorbed photon), respectively. The relatively narrow range of values indicates the stability of AZX with respect to photodegradation in the studied pH range. Results from the HPLC/MS analysis suggest that the phototransformation of AZX proceeds via multiple, parallel reaction pathways including: (1) photo-isomerization (E → Z), (2) photo-hydrolysis of the methyl ester and of the nitrile group, (3) cleavage of the acrylate double bond, (4) photohydrolytic ether cleavage between the aromatic ring giving phenol, and (5) oxidative cleavage of the acrylate double bond.
Preparation method of 4, 6-dihydroxypyrimidine
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Page/Page column 0029-0069, (2020/04/02)
The invention provides a preparation method of 4, 6-dihydroxypyrimidine. The preparation method comprises the steps of carrying out a first-stage reaction, recovering reaction byproducts, carrying outa second-stage reaction, carrying out dissolving, recovering a solvent, and carrying out adsorbing. According to the preparation method, the raw materials comprise diester malonate, formamide and analkali metal alcoholate solution, and the mass content of the alkali metal alcoholate in the alkali metal alcoholate solution is 30%-50%. The preparation process of the 4, 6-dihydroxypyrimidine is a process of recovering a solvent by adopting normal-pressure reaction and negative-pressure distillation, and positive-pressure operation is avoided in the whole process on the premise of ensuring the yield and quality of the product, so that the preparation process is simple and easy to implement, and industrial production is easy to realize. According to the invention, a suitable sodium methoxideconcentration is selected according to the specific ratio relationship of dimethyl malonate, formamide and sodium methoxide, such that the material consumption is further reduced and the product yieldis improved on the premise of ensuring qualified product quality.