(3-Dibenzylamino-2-hydroxy-5-methyl-hexyl)-phosphonic acid dimethyl ester → Phosphonic acid, P-(3-amino-2-hydroxy-5-methylhexyl)-, dimethyl ester

Reaction 4: A diastereomeric mixture of the crude (3-dibenzylamino-2-hydroxy-5-methyl-hexyl)-phosphonic acid dimethyl ester, compound 4, obtained in reaction 3, was treated with palladium-carbon (2.0% wt) as the catalyst in methanol (40 mL). The mixture reaction was stirred for 12 h under a hydrogen gas atmosphere at 37-42° C., and after this period of time, the mixture was filtered through a pad of Celite, and the solvents were removed under reduced pressure to leave (3-amino-2-hydroxy-5-methyl-hexyl)-phosphonic acid dimethyl ester, compound 5 as a crude oil.