Hydrochloric Acid → 2-allyl-3-hydroxy-5-[(tetrahydro-2H-pyran-2-yl)oxy]hexadecanoic acid

Temperature

-50 °C

C)a) 2 ml of diisopropylamine in 30 ml of dry THF were cooled to -20° C. and thereupon 9.68 ml of butyl lithium (1.6M/hexane) were added dropwise in such a manner that the temperature did not exceed -20° C. The mixture was subsequently stirred for 15 minutes and then cooled to -50° C. Thereafter, 0.720 ml of 4-pentenoic acid in 10 ml of THF was added dropwise and the mixture was stirred at 50° C. for a further 10 minutes. The mixture was stirred at room temperature for 1 hour and subsequently again cooled to -50° C. 2 g of rac-3-[(tetrahydro-2H-pyran-2-yl)oxy]-tetradecanal in 10 ml of THF were now added dropwise and the mixture was stirred at -50° C. for a further 30 minutes, then at room temperature for 72 hours. After hydrolysis with 2N hydrochloric acid the reaction mixture was evaporated. The residue was extracted with ether. The organic phase was dried over sodium sulfate, filtered and evaporated. The material obtained was filtered through a column of silica gel. There was obtained 2-allyl-3-hydroxy-5-[(tetrahydro-2H-pyran-2-yl)oxy]hexadecanoic acid.

1. customdid not exceed -20° C
2. stirringthe mixture was stirred at 50° C. for a further 10 minutes
3. stirringThe mixture was stirred at room temperature for 1 hour
4. temperaturesubsequently again cooled to -50° C
5. stirringthe mixture was stirred at -50° C. for a further 30 minutes
6. waitat room temperature for 72 hours
7. customwas evaporated
8. extractionThe residue was extracted with ether
9. dry with materialThe organic phase was dried over sodium sulfate
10. filtrationfiltered
11. customevaporated
12. customThe material obtained
13. filtrationwas filtered through a column of silica gel

ORD record

ord-879d85c422674bbdb657f5a7f9e3d453

Source dataset

uspto-grants-1993_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05246960