78-38-6Relevant articles and documents
Synthesis and selected reactions of 4-(Diethoxyphosphorylmethyl)-3-furoic acid
Pevzner
, p. 404 - 412 (2012)
Reduction of 4-(ethoxycarbonyl)-3-furoyl chloride with sodium borohydride in dioxane-DMF mixture leads to an ethyl 4-hydroxymethylfuran-3-carboxylate. The treatment of the latter with thionyl chloride at boiling yields the corresponding chloromethyl derivative. The obtained chloride reacts with one equivalent of sodium iodide in acetone at room temperature to form iodomethylfuran. Halomethylfurans synthesized are phosphorylated with sodium diethyl phosphite and triethyl phosphite to give ethyl 4- (diethoxyphosphorylmethyl)- 3-carboxylate. The hydrolysis of this substance with one equivalent of potassium hydroxide in ethanol gives the corresponding furoic acid. Treating this substance in succession with ethyl chloroformate and sodium azide yields furoyl azide which while heating in toluene undergoes rearrangement to phosphorus-containing 3- furylisocyanate. Heating the latter with a mixture of acetic acid and acetic anhydride gives N-[4- (diethoxyphosphorylmethyl) furyl-3]acetamide. 4-(Diethoxyphosphorylmethyl)-3- furoic acid reacts with thionyl chloride to form the corresponding furoyl chloride. Its reduction with sodium borohydride in dioxane-DMF mixture leads to the phosphorylated 3-furylmethanol. Aminomethylation of its acetate with dimethylmethyleneiminium chloride in acetonitrile does not proceed at the ring. Instead of that the unstable ester of 3-(dimethylamino) propionic acid and the phosphorylated 3-furylmethanol are formed. In slightly basic medium free Mannich base decomposed to give the starting acetate. Pleiades Publishing, Ltd., 2012.
Synthesis of dl-7-methyldemethylvariotin
Sakakibara,Yamamoto,Matsui
, p. 1507 - 1509 (1978)
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Intensified Continuous Flow Michaelis-Arbuzov Rearrangement toward Alkyl Phosphonates
Monbaliu, Jean-Christophe M.,Toupy, Thomas
supporting information, p. 467 - 478 (2022/02/25)
Herein is described the development of an intensified continuous flow process for the preparation of a library of alkyl phosphonates through a Michaelis-Arbuzov rearrangement. A careful process optimization and thorough analysis of the competitive reactions led to a very attractive protocol with unprecedented productivities (up to 4.97 kg of material per day) and a low environmental footprint with the absence of solvent, additives, catalysts, and waste. In-line low-field 31P NMR monitoring was conveniently implemented for rapid optimization and process monitoring. Two key alkyl phosphonate intermediates were also assessed for the unprecedented diazene dicarboxylate-mediated electrophilic amination under continuous flow conditions toward the α-aminophosphonic acid derivatives of Pphenylalanine and Palanine, bioisosters of the natural amino acids phenylalanine and alanine, respectively.
Microwave-assisted ionic liquid-catalyzed selective monoesterification of alkylphosphonic acids—an experimental and a theoretical study
ábrányi-Balogh, Péter,Drahos, László,Harsági, Nikoletta,Henyecz, Réka,Keglevich, Gy?rgy
, (2021/09/07)
It is well-known that the P-acids including phosphonic acids resist undergoing direct es-terification. However, it was found that a series of alkylphoshonic acids could be involved in mo-noesterification with C2–C4 alcohols under microwave (MW) irradiation in the presence of [bmim][BF4] as an additive. The selectivity amounted to 80–98%, while the isolated yields fell in the range of 61–79%. The method developed is a green method for P-acid esterification. DFT calculations at the M062X/6–311+G (d,p) level of theory (performed considering the solvent effect of the corresponding alcohol) explored the three-step mechanism, and justified a higher enthalpy of activation (160.6–194.1 kJ·mol–1) that may be overcome only by MW irradiation. The major role of the [bmim][BF4] additive is to increase the absorption of MW energy. The specific chemical role of the [BF4] anion of the ionic liquid in an alternative mechanism was also raised by the computations.
Preparation method of phosphorus flame retardant diethyl ethylphosphonate
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Paragraph 0018-0021, (2020/04/22)
The invention provides a preparation method of a phosphorus-based flame retardant diethyl ethylphosphonate, and the method comprises the following steps: mixing phosphorus trichloride, organic amine and petroleum ether, dropwisely adding absolute ethyl alcohol, and carrying out heat preservation reaction to obtain diethyl ethylphosphonate after the reaction is finished. The method is low in reaction temperature, short in reaction time and low in raw material cost, so that compared with the prior art, the method has the advantages of low energy consumption and low production cost.
