(-)-Mandelic acid → HCID 11729384, compound

Participants

Reaction Steps

(R)-(-)-Mandelic acid (11.50g, 75.6 mmol) was added to a suspension of 28.55 g (68.7 mmol) of (±)-3-((αR*)-α-((2R*,5S*)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-bromobenzyl)phenol (Example 84, infra) in 450 mL of absolute ethanol. The mixture was heated to complete solution and then allowed to crystallize at room temperature. Crystals were collected and recrystallized from absolute ethanol. The crystalline mandelate salt was treated with excess 1N aqueous sodium hydroxide and then titrated to pH 8 with 6N hydrochloric acid. The precipitated free amine was recrystallized from absolute ethanol to give 6.25 g (44% of theoretical for one enantiomer) of (+)-3-((αS)-α-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-bromobenzyl)-phenol as a white solid, mp 205°-206° C. [α]D20 =+20° (methanol, c=2). Calc. for C22H27BrN2O: C, 63.62; H, 6.55; N, 6.74; Br, 19.24. Found: C, 63.63; H, 6.57; N, 6.68; Br, 19.16.

Provenance & Evidence