Reacción #2071

Ecuación de reacción

tetraethyl N-benzoyl-5-aminopentane-1,1-bisphosphonate

borane methylsulfide

HCl

→

title compound

Rendimiento 45.8%

tetraethyl N-benzyl-5-aminopentane-1,1-bisphosphonate

Rendimiento 45.8%

Disolventes

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawarmed to 65° C. for 2.5 hours
2. 2
   TemperaturaThe reaction mixture was cooled to 0° C.
3. 3
   OtroThe solvent was removed in vacuo
4. 4
   Concentraciónthe residue was concentrated repeatedly from methanol (2×5 mL)
5. 5
   workup.DISSOLUTIONThe residue was dissolved in water (10 ml)
6. 6
   Extracciónextracted with diethyl ether (3×5 ml)
7. 7
   ExtracciónThe product was extracted into dichloromethane (5×20 ml)
8. 8
   Secadodried (Na2SO4)
9. 9
   Concentraciónconcentrated

Procedimiento

A solution of tetraethyl N-benzoyl-5-aminopentane-1,1-bisphosphonate (0.63 g, 1.36 mmol) in THF (3.4 mL) was cooled to 0° C., and borane methylsulfide (0.34 ml, 3.4 mmol) was added via syringe. The reaction was stirred at 0° C. for 20 minutes, then warmed to 65° C. for 2.5 hours. The reaction mixture was cooled to 0° C. and 6N HCl (4.0 ml) was added carefully. The solvent was removed in vacuo, and the residue was concentrated repeatedly from methanol (2×5 mL). The residue was dissolved in water (10 ml) and extracted with diethyl ether (3×5 ml). The aqueous layer was made basic to phenolphthalein with solid KOH and saturated with NaCl. The product was extracted into dichloromethane (5×20 ml), dried (Na2SO4) and concentrated to give the title compound (0.28 g).

Fuente