Reaction #2069

Reaction equation

N-butyl-3,3-bis(diethoxyphosphinyl)propionamide

borane methyl sulfide

HCl

→

Compound

Yield 109.0%

3-(butylamino)propane-1,1-bisphosphonic acid

Yield 109.0%

Solvents

THF

Conditions

Workup

1. 1
   Temperaturewarmed to 65° C. for 3 hours
2. 2
   TemperatureThe reaction mixture was cooled to 0° C.
3. 3
   OtherThe solvent was removed in vacuo
4. 4
   Concentrationthe residue was repeatedly concentrated from methanol (3×10 mL)
5. 5
   workup.DISSOLUTIONThe product was dissolved in 12N HCl
6. 6
   Temperatureheated
7. 7
   Temperatureat reflux for 20 hours
8. 8
   TemperatureAfter cooling
9. 9
   Otherthe volatile materials were removed under vacuum
10. 10
    workup.DISSOLUTIONthe residue was dissolved in water (10 mL)
11. 11
    Concentrationconcentrated

Procedure

A solution of N-butyl-3,3-bis(diethoxyphosphinyl)propionamide (1.40 g, 3.5 mmol) in THF (9 mL) was cooled to 0° C., and borane-methyl sulfide (0.90 ml, 9.0 mmol) was added via syringe. The reaction was stirred at 0° C. for 5 minutes, then warmed to 65° C. for 3 hours. The reaction mixture was cooled to 0° C. and 6N HCl (6 ml) was added carefully. The solvent was removed in vacuo, and the residue was repeatedly concentrated from methanol (3×10 mL). The product was dissolved in 12N HCl and heated at reflux for 20 hours. After cooling, the volatile materials were removed under vacuum, the residue was dissolved in water (10 mL) and then concentrated to give 1.05 g of Compound No. 158 as a hygroscopic glass.

Source