Borane;tetrahydrofuran → HCID 57440699, compound

Temperature

85 °C

Borane-tetrahydrofuran complex (1M in THF) (3 mL, 3 mmol) was added dropwise to the product from example 45 (0.33 g, 1.18 mmol) in dry THF (4 mL) under an atmosphere of nitrogen. The reaction mixture was heated at 85° C. for 3 hours then cooled and quenched by the addition of methanol (1 mL). The reaction mixture was then concentrated in vacuo and the residue suspended in 6N HCl (aq) (10 mL) and heated to 60° C. for 1.5 hours. The reaction mixture was cooled and extracted with diethyl ether (2×10 mL). The aqueous layer was rendered basic (pH 9-10) by addition of solid potassium carbonate before re-extracting with dichloromethane (2×15 mL). The dichloromethane extracts were dried over anhydrous magnesium sulphate, filtered and concentrated in vacuo to give the crude products as a clear oil. Purification by column chromatography on silica eluting with ethyl acetate, pentane (1:10) yielded the two title compounds as single diastereomers.

1. temperaturethen cooled
2. customquenched by the addition of methanol (1 mL)
3. concentrationThe reaction mixture was then concentrated in vacuo
4. temperatureheated to 60° C. for 1.5 hours
5. temperatureThe reaction mixture was cooled
6. extractionextracted with diethyl ether (2×10 mL)
7. additionby addition of solid potassium carbonate
8. extractionbefore re-extracting with dichloromethane (2×15 mL)
9. dry with materialThe dichloromethane extracts were dried over anhydrous magnesium sulphate
10. filtrationfiltered
11. concentrationconcentrated in vacuo
12. customto give the crude products as a clear oil
13. customPurification by column chromatography on silica eluting with ethyl acetate, pentane (1:10)
14. customyielded the two title compounds as single diastereomers

ORD record

ord-b7426d40d5b54216b3840343d1629191

Source dataset

uspto-grants-2009_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07576081B2