Diethyl Oxalate → HCID 64919879, compound

Temperature

-78 °C

165 mL of an 1 M solution of bis(trimethylsilyl)lithiumamid in THF (166 mmol, 1.10 eq.) were brought forward in 500 mL of diethyl ether and cooled down to −78° C. 14.8 g of 1-cyclopropylpropan-1-one 1-12-1 was dissolved in 100 mL of diethyl ether and added dropwise at −78° C. The mixture was stirred for one hour at −78° C. and then 24.5 mL of diethyl oxalate was added dropwise. The cooling bath was removed and the mixture was stirred for 24 hours at rt. 500 mL of aqueous 1M hydrogen chloride solution was added and the mixture was extracted with DCM, dried over a silicone filter sulfate and concentrated in vacuo to provide 27.2 g (137 mmol, 91%) of the target compound as crude product. The crude product was used for the following step without further purification.

1. additionadded dropwise at −78° C
2. customThe cooling bath was removed
3. stirringthe mixture was stirred for 24 hours at rt
4. addition500 mL of aqueous 1M hydrogen chloride solution was added
5. extractionthe mixture was extracted with DCM
6. dry with materialdried over a silicone
7. filtrationfilter sulfate
8. concentrationconcentrated in vacuo

ORD record

ord-ce23525e522e48bdb59179af1c7a1145

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09260412B2