3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → tert-Butyl 3-methylideneazetidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a suspension of methyltriphenylphosphonium bromide (1.56 g, 4.37 mmol) in 30 mL of Et2O stirred at 0° C. was added potassium tert-butylate (0.459 g, 4.09 mmol). After 0.5 h the cold bath was removed and the mixture was stirred for 1 h at r.t. Afterwards, it was cooled off in water-ice bath, and 3-oxo-azetidine-1-carboxylic acid tert-butyl ester (500 mg, 2.92 mmol) was added. The cold bath was removed. After overnight resting, the reaction mixture was quenched with a saturated solution of NH4Cl in water, extracted with Et2O, dried on Na2SO4, evaporated to dryness in vacuo, dissolvent. The residual crude was purified by automated flash chromatography (SP1®TM-Biotage; gradient Petroleum Ether-Acetone from 10:0 to 7:3) to give the title compound (426 mg) as a dense colourless oil. Yield: 86.2%

Provenance & Evidence