Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 1128-00-3, name is Ethyl 2-aminocyclohex-1-enecarboxylate, A new synthetic method of this compound is introduced below., category: esters-buliding-blocks
General procedure: 5-phenylpent-2-enoic acid (13) (0.18 g, 1.02 mmol) in DCM(2 ml) under argon atmosphere at rt was treated with a catalytic amount of DMF (1 drop) and oxalyl chloride (0.26 ml, 3.06 mmol). The mixture was stirred for 40 min and the volatiles were evaporated. The residue was dissolved in DCM (2 ml) and to the obtained solution at 0 C a mixture of ethyl 2-aminocyclohex-1-ene-1-carboxylate(0.26 g, 1.54 mmol) and triethylamine (0.14 ml,1.00 mmol) in DCM (1 ml) was added dropwise over 5 min. The mixture was stirred for 40 min at rt, then the mixture was supplemented with DCM, washed with saturated NH4Cl solution, brine,dried over Na2SO4, and concentrated. The residue was chromatographed on silica gel (EtOAc in petroleum ether, 1:10 to1:6) to give crude ethyl (E)-2-(5-phenylpent-2-enamido)cyclohex-1-ene-1-carboxylate (0.21 g) as a colorless oil. 1H NMR(300 MHz, CDCl3) d: 11.71 (s, 1H), 7.33-7.16 (m, 5H), 6.92 (dt,J = 15.3, 6.8 Hz, 1H), 5.92 (dt, J = 15.3, 1.5 Hz, 1H), 4.19 (q,J = 7.1 Hz, 1H), 3.09-2.98 (m, 2H), 2.85-2.69 (m, 2H), 2.59-2.45(m, 2H), 2.39-2.25 (m, 2H), 1.73-1.56 (m, 4H), 1.30 (t, J = 7.1 Hz,3H). LCMS (ESI) m/z: 328.37 [M+H]+. The oil was dissolved in a mixture of THF (2 ml) and EtOH (1 ml) and to the obtained solution 2 N NaOH (0.92 ml, 1.84 mmol) was added. The mixture was stirred for 16 h at rt followed by stirring for 5 h at 50 C. The reaction mixture was cooled to rt and acidified to pH 4 with 1 N HCl. The solvents were evaporated and the residue was partitioned between DCM and water. The organic layer was dried over Na2SO4, evaporated, and the residue was chromatographed on silica gel (MeOH in DCM, 1:20) to give an oily solid. The solid was triturated with EtOAc petroleum ether mixture (1:4), filtered, and dried in vacuo to give the product 3 (44 mg, 14%, calculated with respect to 13) as white crystals.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Article; Bobileva, Olga; Ikaunieks, Martins; Duburs, Gunars; Mandrika, Ilona; Petrovska, Ramona; Klovins, Janis; Loza, Einars; Bioorganic and Medicinal Chemistry; vol. 25; 16; (2017); p. 4314 – 4329;,
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