Ethyl 2-Oxo-1-pyrrolidineacetate (43). A suspension of sodium hydride (57%) in mineral oil, 45 g, 1.07 mol) in tetrahydrofuran (1.5
L) was stirred, and a solution of 2-pyrrolidinone (Aldrich Chemical Co.; 85 g, 1.0 mol) in tetrahydrofuran (200 mL) was added in slow stream). After
the hydrogen gas evolution had subsided, the mixture was heated to reflux, and ethyl 2-bromoacetate (Eastman Kodak; 184 g, 1.1 mol) was added
dropwise. The mixture was refluxed for 16 h, cooled, and diluted with diethyl ether, 2 L. The resulting slurry was filtered to remove solids and
concentrated on a rotary evaporator. The resulting two-phase oil was washed twice with petroleum ether (500 mL) and carefully distilled to yield 130
g (76%) of 43, bp 140-145*C (20 mm). Anal. (C8H13NO3) C, H, N.
N-[2-[Bis(1-methylethyl)amino]ethyl]-2-oxo-1-pyrrolidineacetamide (8). A solution of ethyl 2-oxo-1-pyrrolidineacetate
(43; 17.1 g, 0.1 mol) in N,N-bis(1-methylethyl)-1,2-ethanediamine (Ames Laboratories; 28.8 g, 0.2 mol) was heated at 100*C with
stirring for 16 h, removing ethanol as it was produced. The mixture was concentrated to an oil on the rotary evaporator and was rapidly distilled
through a short Vigreaux column to yield 18.6 g (69%) of 8, bp 162-164*C (0.15 mm). Anal. (C14H27N3O2) C, H, N.
|