Diethyl Malonate → diethyl [(1,1-dimethylethoxycarbonyl)methyl]-malonate

Diethyl malonate (31.15 g, 194.48 mmoles) was first transferred at 0° C. to a stirring suspension of sodium hydride (4.67 g, 194.58 mmoles) in dry THF (200 mL). To this resulting mixture, was added dropwise (at 0° C.) a solution of t-butyl bromoacetate (23.00 g, 117.91 mmoles). Formation of a white precipitate was instantly observed. The mixture was then stirred at room temperature until complete consumption of the starting material (1.5 hours as confirmed by TLC: 20% ethyl acetate: 80% hexanes). The solvent was then evaporated and the residue was taken-up in 500 mL diethyl ether. This organic phase was washed with water (3×300 mL) and washed once with brine (200 mL) before being dried (anhydrous MgSO4) and evaporated. The obtained residue was first purified by distillation to remove excess malonate and then by flash chromatography (SiO2, 15% ethyl acetate: 85% hexanes) to afford 30.00 g (92.8% yield) of the desired compound as an oil: IR (film) 2982, 1733, 1258, 1152, 1037 cm−1; 13C NMR (CDCl3, 100 MHz) 169.5, 168.1, 80.8, 61.2, 47.7, 33.9, 27.6.

1. customThe solvent was then evaporated
2. washThis organic phase was washed with water (3×300 mL)
3. washwashed once with brine (200 mL)
4. dry with materialbefore being dried (anhydrous MgSO4)
5. customevaporated
6. distillationThe obtained residue was first purified by distillation
7. customto remove excess malonate

ORD record

ord-54417c4adadc48e6a111f27e6f523160

Source dataset

uspto-grants-2008_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07365091B2