Pseudoephedrine → Pseudoephedrine

Participants

Reaction Conditions

Reaction Steps

A solution of 1-[2-(tert-butoxycarbonyl)-3-(2-methoxyethoxy)propyl]-1-cyclopentanecarboxylic acid (110.1 g, 0.333 mole) in hexane (550 ml) was treated with (+) pseudoephedrine (55.1 g, 0.333 mole) and the mixture was heated to reflux. The resulting solution was cooled to induce crystallisation, and stirred at 5° C. for 1 hour to granulate the crystals. After overnight refrigeration at 5° C., filtration, washing with hexane (200 ml) and drying gave the crude (+) pseudoephedrine salt of the (S) acid (89.9 g, 54.4%) as a white solid m.p. 76°-80° C. Recrystallisation of 30 g of this material twice from hexane (225 ml) gave the (+)pseudoephedrine salt of the title compound (21.45 g, 71.5% recovery) as white crystals m.p. 86°-7° C., [α]D +34.9° (c=1, MeOH). Found: C,65.21; H,9.23; N,2.91. C27H45NO 7 requires C,65.42; H,9.15; N,2.82%.

Provenance & Evidence