Diethyl Malonate → Diethyl 2-(2-nitro-4-(4-nitrobenzoyl)phenyl)malonate

Temperature

100 °C

NaH, 60% dispersion in mineral oil, (1.27 g, 31.7 mmol) was washed with petroleum ether then suspended in anhydrous DMSO (30 mL). Diethyl malonate (4.85 mL, 31.7 mmol) was dissolved in 8 mL of anhydrous DMSO and added dropwise to the NaH suspension. The mixture was allowed to stir for 15 min at 100° C., during which time the reaction mixture became homogeneous. (4-Bromo-3-nitro-phenyl)-(-4-nitro-phenyl)-methanone (5.15 g, 14.4 mmol) was dissolved in anhydrous DMSO (15 mL) and subsequently added via syringe to the malonate solution. The mixture was allowed to stir at 100° C. for 2 h after which the reaction was cooled to room temperature and poured into water (˜300 mL). The mixture was extracted with EtOAc (3×300 mL) and dried over anhydrous Na2SO4. The organic layers were then concentrated in vacuo affording a crude black oil. The crude oil was then flashed through a plug of silica with 30% EtOAc/Hexanes. The solution was then concentrated in vacuo yielding a pale yellow solid that contained the desired product contaminated with excess diethyl malonate. The impure solid was washed with Hexanes, filtered and dried affording diethyl [2-nitro-4-(4-nitrobenzoyl)phenyl]malonate in 75% yield (4.64 g, 10.8 mmol).

1. washNaH, 60% dispersion in mineral oil, (1.27 g, 31.7 mmol) was washed with petroleum ether
2. stirringto stir at 100° C. for 2 h after which the reaction
3. temperaturewas cooled to room temperature
4. extractionThe mixture was extracted with EtOAc (3×300 mL)
5. dry with materialdried over anhydrous Na2SO4
6. concentrationThe organic layers were then concentrated in vacuo
7. customaffording a crude black oil
8. concentrationThe solution was then concentrated in vacuo
9. customyielding a pale yellow solid

ORD record

ord-c4c7cde3cb8d4aa2983e2e8cef0dd4ef

Source dataset

uspto-grants-2010_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07692005B2