Water → 2,5-Dioxopyrrolidin-1-yl 2-(trimethylsilyl)ethyl carbonate

2-Trimethylsilylethyl carbonochloridate (4.8 g, 26.9 mmol) was taken up in dry acetronitrile (50 mL). The solution was cooled to 0° and solid N-hydroxysuccinimide (4.0 g, 34.8 mmol) was added with vigorous stirring followed by a solution of dry triethylamine (3.2 g, 31.6 mmol) in dry acetonitrile (5 mL). The mixture was stirred at low temperature for 15 minutes, then at room temperature overnight. The mixture was poured into water (200 ml) and extracted with ether (4×50 mL). The organic extracts were combined, washed with water (2×60 mL), 1 normal hydrochloric acid (60 mL), again water (60 mL), brine (60 mL), dried with magnesium sulfate and evaporated to dryness. The residue was taken up in boiling hexane (200 mL) and the solution allowed to cool. Crystallization was completed by storage at −15° C. (yield: 1.70 g).

1. temperatureThe solution was cooled to 0°
2. stirringThe mixture was stirred at low temperature for 15 minutes
3. customat room temperature
4. customovernight
5. extractionextracted with ether (4×50 mL)
6. washwashed with water (2×60 mL), 1 normal hydrochloric acid (60 mL), again water (60 mL), brine (60 mL)
7. dry with materialdried with magnesium sulfate
8. customevaporated to dryness
9. temperatureto cool
10. customCrystallization
11. customwas completed by storage at −15° C.

ORD record

ord-d45cd3ac90394dd48dc69482190fb25b

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06627660B1