Ethyl chloroformate → HCID 86682563, compound

Participants

Reaction Conditions

Reaction Steps

4-pentynoic acid (2.01 g) and hexamethylphosphoamide (6.99 mL) were dissolved in 80 mL of THF, and LDA (20.1 mL) was added dropwise over 20 minutes while stirring at −78° C. After this solution was stirred at −78° C. for 1 hour, a solution of ethyl chloroformate (2.18 g) in 20 mL of THF was added dropwise over 15 minutes, and the mixture was stirred at that temperature for 30 minutes. Thereafter, acetic acid (1.15 mL) was added, a temperature was raised to room temperature, a 10% aqueous potassium dihydrogen phosphate solution was added, and extraction operation (THF once, tetrabutyl methyl ether two times) was performed. After the resulting organic layer was dried with magnesium sulfate, the solvent was distilled off under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography (A/B=30%→45%, A=ethyl acetate: acetic acid=30:1, B=n-hexane) to obtain the title compound (641 mg) having the following physical property values.

Provenance & Evidence