Acetone → HCID 20446887, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1-p-tolyl-3-(t-butyldimethylsiloxy)-pyrazoline (218 g, 0.75 mole) in 750 ml anhydrous tetrahydrofuran was added dropwise over a 30 minute period to a solution of n-butyllithium (51.5 g, 0.80 mole) in 350 ml n-hexane and 3.0 l anhydrous tetrahydrofuran stirred under nitrogen and cooled to -78° C. in a dry ice-acetone bath. The mixture was stirred for another 30 minutes then treated with one portion of acetone (58. g, 1.0 mole), and stirred at -78° C. for an additional 30 minutes. After removal of the dry ice-acetone bath, one portion of 250 ml 5% aqueous hydrochloric acid was added and the mixture was stirred an additional 25 minutes. The mixture was extracted with 1.0 l of ether and then with a (1:1) mixture of ether and ethyl acetate. The combined extracts were dried over magnesium sulfate. After removal of solvent, the residue was digested in a hot (3:2) mixture of ether and n-hexane. Upon cooling to 0° C. and filtering, 111 g of 4-(1-hydroxy-1-methylethyl)-1-p-tolyl-3-pyrazolidinone was obtained. Analysis was confirmed by infrared and NMR spectra.

Provenance & Evidence