tert-BUTYL CHLORIDE → 3,4-Hexanedione, 2,2,5,5-tetramethyl-

Temperature

-65 °C

26.44 mL (0.240 moles) 2-chloro-2-methyl propane was slowly added to 5.76 g, (0.240 moles) of magnesium turnings in 240 mL of tetrahydrofuran to make the Grignard reagent, t-BuMgCl. The freshly prepared Grignard reagent was slowly added to a mixture of 34 g (0.240 moles) copper bromide and 41 g (0.480 moles) of lithium bromide in 270 mL of tetrahydrofuran (THF), cooled to −65° C. 8.72 mL (0.10 moles) of oxalyl chloride in 30 mL of THF was then added slowly, maintaining mixture temperature at −65° C. The resulting mixture was stirred for an hour at −65° C., then warmed up to room temperature overnight. 90% of the THF is removed by vacuum, followed by the addition of 500 ml of hexane and 300 ml of a saturated aqueous solution of ammonium chloride. The hexane layer was separated and the aqueous layer extracted with three 200 ml lots of hexane. The hexane layers were then combined and washed with water prior to drying with 10 g of anhydrous magnesium sulfate. The mixture was then filtered and the hexane distilled off under atmospheric pressure to yield the product as a yellow oil. Yield=10.5 g (53% of theoretical)

1. temperaturemaintaining mixture temperature at −65° C
2. temperaturewarmed up to room temperature overnight
3. custom90% of the THF is removed by vacuum
4. additionfollowed by the addition of 500 ml of hexane and 300 ml of a saturated aqueous solution of ammonium chloride
5. customThe hexane layer was separated
6. extractionthe aqueous layer extracted with three 200 ml lots of hexane
7. washwashed with water
8. dry with materialto drying with 10 g of anhydrous magnesium sulfate
9. filtrationThe mixture was then filtered
10. distillationthe hexane distilled off under atmospheric pressure

ORD record

ord-a49079f029844e9a98c204334305623c

Source dataset

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08680289B2