Dimethyl Sulfoxide → 1-Butanone, 3-methyl-1-pyrazinyl-

HRID 717595Notes

Reaction equation

C(Cl)(=O)C(Cl)=O.CS(C)=O.[CH3:11][CH:12]([CH3:22])[CH2:13][CH:14]([C:16]1[CH:21]=[N:20][CH:19]=[CH:18][N:17]=1)[OH:15].C(N(CC)CC)C>ClCCl.O>[CH3:11][CH:12]([CH3:22])[CH2:13][C:14]([C:16]1[CH:21]=[N:20][CH:19]=[CH:18][N:17]=1)=[O:15]

Participants

Conditions

Temperature: -60 °C

Procedure

A solution of oxalylchloride (2.65 mL, 3.92 g, 30.9 mmol) in dichloromethane (50 mL) was cooled to −60° C. and DMSO (4.4 mL, 4.82 g, 4.4 mL) was added while maintaining the temperature between −50 and −60° C. A solution of 3-methyl-1-(pyrazin-2-yl)butan-1-ol (4.66 g, 28.0 mmol) in dichloromethane (10 mL) was added and the mixture was stirred for 15 min at −60° C. Triethylamine (19.45 mL, 14.17 g, 140 mmol) was added (T≈−55° C.) and the mixture was allowed to reach room temperature. Water was added and the aqueous phase was extracted with dichloromethane. The combined organic layers were dried over MgSO4 and concentrated in vacuo. Column chromatography (silica, EtOAc/Heptane 1/9) afforded 3-methyl-1-(pyrazin-2-yl)butan-1-one as a dark yellow oil (4.3 g; 94%).

Workup

temperaturewhile maintaining the temperature between −50 and −60° C
customto reach room temperature
extractionthe aqueous phase was extracted with dichloromethane
dry with materialThe combined organic layers were dried over MgSO4
concentrationconcentrated in vacuo

Sources & evidence

ORD record: ord-fe22fb22e79244f58fc5bca2dac20d00
Source dataset: uspto-grants-2015_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09193722B2

Reaction notes

Loading…