Borane → HCID 28106109, compound

Temperature

60 °C

Isobutyric anhydride (2.034 mL, 12.25 mmol) was added dropwise to a stirred solution of 4-butyl-2-methylaniline (2 g, 12.25 mmol) and triethylamine (3.41 mL, 24.50 mmol) in dichloromethane (DCM) (20 mL) under nitrogen. The solution was stirred for 20 hours and then treated with 2M HCl (75 mL) and stirred for 5 minutes. The reaction mixture was extracted with DCM and the combined organic layers were dried over magnesium sulfate. The magnesium sulfate was filtered and the DCM phase concentrated in vacuo to gave N-(4-butyl-2-methylphenyl)-2-methylpropanamide (2.402 g, 10.29 mmol, 84% yield). A stirred solution of N-(4-butyl-2-methylphenyl)-2-methylpropanamide (2.402 g, 10.29 mmol) in tetrahydrofuran (30 mL) under nitrogen was treated dropwise with 1M borane in tetrahydrofuran (BH3 in THF, 30.9 mL, 30.9 mmol; obtainable from, for example, Aldrich). The solution was heated at 60° C. for 2 hours before being quenched with 2M HCl (18 mL) and stirred for a further 15 minutes. It was then basified with aqueous Na2CO3 and extracted with DCM (2×150 mL). The combined organic phases were then dried over magnesium sulfate and concentrated in vacuo. The sample was loaded in dichloromethane and purified on Biotage Flashmaster II on silica (Si) 100 g using a 0-100% dichloromethane-cyclohexane over 60 mins. The appropriate fractions were combined and evaporated in vacuo to give 1.66 g of the title compound as a colourless liquid.

1. custombefore being quenched with 2M HCl (18 mL)
2. extractionextracted with DCM (2×150 mL)
3. dry with materialThe combined organic phases were then dried over magnesium sulfate
4. concentrationconcentrated in vacuo
5. custompurified on Biotage Flashmaster II on silica (Si) 100 g
6. customover 60 mins
7. customevaporated in vacuo

ORD record

ord-cc52a3c0304c44b1a469864274551463

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09150508B2