Sodium borohydride → Tetrahydro-2H-pyran-3-ethanol

Temperature

50 °C

A suspension of sodium borohydride (554 mg) in ethanol (20 ml) was cooled (ice bath) and a solution of tetrahydro-2H-pyran-3-ylacetaldehyde (1.88 gm) in ethanol (8 ml) added dropwise with stirring over 10 min. After 15 min the ice bath was removed and after a further 3 h the mixture was heated at 50° C. for 1 h. After cooling the solvent was evaporated and the residue treated with water and extracted three times with dichloromethane. The combined extracts were washed with dilute brine, dried by passing through a hydrophobic frit and evaporated to give the title product as an oil. A further batch of product was obtained by acidifying the aqueous solution with 2N hydrochloric acid, saturating with sodium chloride and extracting three times with dichloromethane. These extracts were treated as above and the batches combined to give a total yield of 1.54 g (81%).

1. temperaturewas cooled (ice bath)
2. customAfter 15 min the ice bath was removed and after a further 3 h the mixture
3. temperatureAfter cooling the solvent
4. customwas evaporated
5. additionthe residue treated with water
6. extractionextracted three times with dichloromethane
7. washThe combined extracts were washed with dilute brine
8. customdried
9. customevaporated

ORD record

ord-1f6ef8a63a014b0ba1a95eed208de9e5

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07977344B2