HCID 53729267, compound → HCID 54571277, compound

Next, the alkali-stable group was converted to a primary hydroxyl group in one of two representative alternative processes. Palladium (10%) on carbon (3.2 g) was added to a Pyrex® hydrogenation vessel and a solution of 5-(R)-acetoxy-1-benzyloxyhexane (65.5 g, 0.26 mole) in acetic acid (65 ml) was added under an argon atmosphere. The reaction vessel was filled with hydrogen gas (75 psi), shaken for five minutes, evacuated, and this process was repeated again and finally the reaction vessel was brought to 75 psi with hydrogen and hydrogenated for 12 hours. Exothermic reaction and rapid absorption of hydrogen was observed during first 2-3 hours. The vessel was replenished with hydrogen whenever the hydrogen was consumed. After 12 hours the reaction mixture was filtered, and the solids were washed with ethyl acetate (75 ml). The combined filtrates were concentrated under reduced pressure and then the residue was dissolved in ethyl acetate (200 ml). The solution was washed with saturated aqueous sodium bicarbonate solution (2×100 ml) and saturated aqueous sodium chloride solution (100 ml) and then dried over magnesium sulfate (10 g). Evaporation of the solvent under reduced pressure gave 39.84 g of 5-(R)-acetoxy-1-hydroxyhexane (yield=95%, 91% pure by gas chromotagraphy).

1. customevacuated
2. waithydrogenated for 12 hours
3. customExothermic reaction and rapid absorption of hydrogen
4. waitwas observed during first 2-3 hours
5. customwas consumed
6. filtrationAfter 12 hours the reaction mixture was filtered
7. washthe solids were washed with ethyl acetate (75 ml)
8. concentrationThe combined filtrates were concentrated under reduced pressure
9. dissolutionthe residue was dissolved in ethyl acetate (200 ml)
10. washThe solution was washed with saturated aqueous sodium bicarbonate solution (2×100 ml) and saturated aqueous sodium chloride solution (100 ml)
11. dry with materialdried over magnesium sulfate (10 g)
12. customEvaporation of the solvent under reduced pressure

ORD record

ord-7e96870eee5943db993184a625267711

Source dataset

uspto-grants-1997_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05629423