N,N,N',N'-Tetramethylethylenediamine → HCID 86740186, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1.42 g of 13 in 25 ml of dry tetrahydrofuran was added drop-by-drop to a solution of lithium hexamethyldisilazide (prepared by adding 5.7 ml of a 2.2M solution of n-butyllithium in hexane drop-by-drop to a solution of 2.7 ml of hexamethyldisilazane and 1.9 ml of tetramethylethylenediamine in tetrahydrofuran) in 15 ml of dry tetrahydrofuran, at -78° C., under argon. The resulting solution was stirred for one hour at -78° C., then a solution of 0.96 g of phenylselenenyl chloride in 15 ml of dry tetrahydrofuran was added rapidly. The resulting solution was stirred at -78° C. for 10 minutes, warmed to -20° C. and quenched by the addition of 60 ml of 1N hydrochloric acid and 20 ml of cold water. The solution then was warmed to room temperature and extracted with ether. The extract was washed, successively, with water, 1N hydrochloric acid, 1N sodium bicarbonate solution and water. It then was dried (MgSO4), the solvent was evaporated and the residue was chromatographed on silica gel, eluting first with n-hexane (to remove diphenylselenide) and then with 30% ethyl acetate/n-hexane to give, on work-up, methyl (S)-4-(benzyloxycarbonylamino)-5-fluoro-2-(phenylselenyl)pentanoate (26A), as a pale yellow oil.

Provenance & Evidence