《Tandem Reaction of 4-Halo-1,3-Dicarbonyl Compounds with Alkynes towards 4-Vinyl-3(2H)-Furanones and 3(2H)-Furanone fused 2-Pyridones》 was written by Omanakuttan, Vishnu K.; Santhini, P. V.; Shaludheen, S.; Varughese, Sunil; Hopf, Henning; John, Jubi. Safety of Ethyl propiolateThis research focused onvinyl furanone preparation; furanone fused pyridone preparation; halo dicarbonyl compound alkyne tandem Michael addition intramol cyclization. The article conveys some information:
A facile synthetic route of 4-vinyl-3(2H)-furanones I [R1 = OMe, OEt, OtBu, Ph; R2 = H, C(O)Ph, CO2Me, CO2tBu; R3 = H, Me; R4 = H, Me, Br; R5 = OMe, OEt, Ph] via tandem Michael addition and intramol. cyclization from the reaction of 4-halo-1,3-dicarbonyl compounds and alkynes was reported. The formation of a side-product (regioisomer) by a stepwise [2+2] cycloaddition between enolate (of the 4-halo-1,3-dicarbonyl compound) and activated alkyne followed by a sequential 4π-ring opening and an intramol. cyclization was also noted. Another interesting observation was the formation of 3(2H)-furanone fused 2-pyridone II [R6 = Me, Et; R7 = Ph, Bn, 4-MeC6H4, etc.] from the reaction of 4-bromo-3-oxo-N-alkyl(aryl)butanamides and activated alkynes with satisfactory to good yields. After reading the article, we found that the author used Ethyl propiolate(cas: 623-47-2Safety of Ethyl propiolate)
Ethyl propiolate(cas: 623-47-2) is a clear colorless to pale yellow liquid that is soluble in ethanol, ether and chloroform. It an important organic chemical raw material and pharmaceutical intermediate. Ethyl propargylate is obtained by oxidation of propargyl alcohol to propargylic acid followed by esterification.Safety of Ethyl propiolate
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