Trimethylaluminum → HCID 68869399, compound

To a 2M solution of trimethylaluminum in dichloromethane (30 mL) was added slowly a solution of methyl N-(3-aminopropyl)-N-(tert-butoxycarbonyl)-D-alaninate (11.5 g) in dichloromethane. The reaction mixture was stirred at room temperature for four days and then poured into a flask containing 30 g of Celite. The mixture was stirred and quenched by the slow addition of ˜10 mL of saturated aqueous ammonium chloride solution. Sodium sulfate (20 g) and methanol (50 mL) were added. The mixture was stirred for 1 h, then filtered. The solids were washed with 5% methanol/dichloromethane. The filtrate was concentrated. The residue was purified by flash chromatography (silica gel, eluting sequentially with 4, 6, 7 and 12% of 10:1 methanol/aqueous concentrated ammonium hydroxide in dichloromethane) to provide the title compound containing less than 3% of the (3S)-isomer.

1. additionpoured into a flask
2. additioncontaining 30 g of Celite
3. stirringThe mixture was stirred
4. customquenched by the slow addition of ˜10 mL of saturated aqueous ammonium chloride solution
5. additionSodium sulfate (20 g) and methanol (50 mL) were added
6. stirringThe mixture was stirred for 1 h
7. filtrationfiltered
8. washThe solids were washed with 5% methanol/dichloromethane
9. concentrationThe filtrate was concentrated
10. customThe residue was purified by flash chromatography (silica gel
11. washeluting sequentially with 4, 6, 7 and 12% of 10:1 methanol/aqueous concentrated ammonium hydroxide in dichloromethane)

ORD record

ord-28bf36ae1d9a4dbca329acdd949734e8

Source dataset

uspto-grants-2006_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07101871B2