Potassium sodium tartarate → (2S,4R)-[4-tert-butoxy-1-(naphthalene-2-sulfonyl)-pyrrolidin-2-yl]-methanol

Participants

Reaction Steps

LAH reduction: To a slurry of lithium aluminium hydride (0.72 g) in Et2O (120 ml) was added a solution of (2S,4R)-4-tert-butoxy-1-(naphthalene-2-sulfonyl)-pyrrolidine-2-carboxylic acid benzyl ester (9.0 g) in Et2O (80 ml) dropwise at −15° C. within 0.5 h. The suspension was stirred for 2 h at the same temperature, then a saturated solution of potassium-sodium tartrate (10 ml) was added dropwise. The slurry was filtered through a pad of filter aid and was washed with Et2O. The combined filtrates were washed with brine, dried over magnesium sulphate and concentrated. The residue was crystallized from acetone/Et2O/hexane to obtain (2S,4R)-[4-tert-butoxy-1-(naphthalene-2-sulfonyl) -pyrrolidin-2-yl]-methanol (6.1 g) as a colorless solid, mp 124–125° C.; MS 363 (M).

Provenance & Evidence