Dimethyl Sulfoxide → 2,2-Difluoro-5-methoxy-1-pentanal hydrate

Temperatur

-60 °C

A solution of dry dimethylsulfoxide (3 g, 38 mmoles) in dry dichloromethane (15 ml) is slowly added to a solution of oxalyl chloride (2.4 g, 19 mmoles) in dichloromethane (15 ml), kept under nitrogen and cooled to -60° C. Stirring is continued for 15 min. at -60° C. and followed by addition of 2,2-difluoro-1-hydroxy-5-methoxypentane (2.7 g, 17.5 mmoles) in dichloromethane (15 ml). The reaction mixture is stirred for 11/2 hours at -60° C., triethylamine (8.4 ml, 114 mmoles) in dichloromethane (15 ml) is slowly added, and the cooling bath is removed. The reaction mixture is hydrolyzed with brine and diluted with dichloromethane. The organic phase is then washed successively with 2N HCl containing some sodium chloride, and brine. Usual work-up affords the title compound (1.59 g, 53%) which is used for the next step without further purification.

1. stirringThe reaction mixture is stirred for 11/2 hours at -60° C.
2. customthe cooling bath is removed
3. additiondiluted with dichloromethane
4. washThe organic phase is then washed successively with 2N HCl containing some sodium chloride, and brine

ORD-Eintrag

ord-7857d77b235a47458505ec6d65fe4927

Quelldatensatz

uspto-grants-1988_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04730006