38345-66-3

Reducing reagent in organic synthesis.

Purify the hydrochloride by dissolving 1.5g in 13.5 mL of 5N HCl, heat to boiling and evaporate in a vacuum. Recrystallise the hydrochloride three times from MeOH/EtOAc giving m 189-190o, []D -33.7o (c 1, H2O) {enantiomer has +34.2o}. The hydrochloride in the minimum volume of water is basified with aqueous 5N NaOH and extracted with Et2O. The extract is dried (K2CO3) and evaporated, leaving a residue which is stored in a desiccator over solid KOH as a low melting solid. It can be recovered using these procedures from asymmetric reductions with LAH, and re-used. [Pohland & Sullivan J Am Chem Soc 77 3400 1955, Sullivan et al. J Org Chem 28 2483 1963, Beilstein 13 IV 2221.]