Diisopropylamine → HCID 178442844, compound

26(b) 69.1 ml of a 15.13% w/w hexane solution of butyllithium was added dropwise to a solution of 15.42 ml of diisopropylamine in 500 ml of tetrahydrofuran at -10° to -15° C., and the mixture was stirred at the same temperature for 15 minutes. To it was added dropwise a solution of 4.95 g of 3-hydroxy-5-methylisoxazole dissolved in 50 ml of tetrahydrofuran at -10° C., and the mixture was stirred at the same temperature for 30 minutes. It was then cooled to -55° C. after which 41.6 g of tetradecyl bromide were added all at once. After removal from the cooling bath, the mixture was stirred for 3 hours, and then 100 ml of diethyl ether were added. The mixture was washed with 150 ml of 5% w/v aqueous hydrochloric acid, and the organic layer was washed with water, dried and concentrated by evaporation under reduced pressure. 100 ml of hexane were added to the residue, and the precipitated solid was collected by filtration and washed with hexane. It was then dried to give crude crystals (13.65 g) of the title compound. Concentration of the filtered hexane solution gave a residue, which was subjected to column chromatography through 100 g of silica gel. Crude crystals (1.40 g) were obtained from the fractions eluted with a 2:1 by volume mixture of methylene chloride and diethyl ether. The combined crude crystals were recrystallized from methylene chloride to give the pure title compound (9.65 g) melting at 82°-83° C. Further crystals (3.91 g) were obtained by concentration of the mother liquor. The spectra of these compounds were identical with those ofthe compound obtained as described in (a) above.

1. stirringthe mixture was stirred at the same temperature for 30 minutes
2. additionwere added all at once
3. customAfter removal from the cooling bath
4. stirringthe mixture was stirred for 3 hours
5. addition100 ml of diethyl ether were added
6. washThe mixture was washed with 150 ml of 5%
7. washthe organic layer was washed with water
8. customdried
9. concentrationconcentrated by evaporation under reduced pressure
10. addition100 ml of hexane were added to the residue
11. filtrationthe precipitated solid was collected by filtration
12. washwashed with hexane
13. customIt was then dried
14. customto give crude crystals (13.65 g) of the title compound
15. customCrude crystals (1.40 g) were obtained from the fractions
16. washeluted with a 2:1 by volume mixture of methylene chloride and diethyl ether
17. customwere recrystallized from methylene chloride

ORD record

ord-1c044958c136478b80dbdcfef5008c66

Source dataset

uspto-grants-1991_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05068340