Development of a Scalable Process for the Insecticidal Candidate Tyclopyrazoflor. Part 2. Fit-for-Purpose Optimization of the Route to Tyclopyrazoflor Featuring [3 + 2] Cyclization of 3-Hydrazinopyridine·2HCl and Methyl Acrylate was written by Yang, Qiang;Li, Xiaoyong;Lorsbach, Beth A.;Muhuhi, Joseck M.;Roth, Gary A.;Gray, Kaitlyn;Podhorez, David E.. And the article was included in Organic Process Research & Development in 2019.Reference of 763-69-9 The following contents are mentioned in the article:
Optimization of the route to the sap-feeding insecticidal candidate tyclopyrazoflor (I) featuring [3 + 2] cyclization of 3-hydrazinopyridine·2HCl and Me acrylate is described. The key impurities in the [3 + 2] cyclization were identified and successfully controlled after optimization. The hazards associated with oxidation of an intermediate pyrazolidin-3-one using the incompatible combination of potassium persulfate and N,N-dimethylformamide (DMF) were avoided by using potassium ferricyanide in the presence of potassium hydroxide in water. The two elimination impurities in the ethylation step to produce tyclopyrazoflor were successfully minimized using Et iodide in the presence of cesium carbonate in DMF at 0 °C. The overall yield for this seven-step synthesis of tyclopyrazoflor was improved from 10% to 41% after the optimization detailed herein. This study involved multiple reactions and reactants, such as Ethyl 3-ethoxypropanoate (cas: 763-69-9Reference of 763-69-9).
Ethyl 3-ethoxypropanoate (cas: 763-69-9) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Reference of 763-69-9
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