Water → N,N-Diethylbenzamide

Participants

Reaction Steps

(±)-4-((αR*)-α-((2R*,5S*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl) -N-N-diethylbenzamide (Example 14) (21.75 g, 0.0499 mol) was dissolved in 330 mL methanol:90 mL water. Trifluoroacetic acid (3.9 mL, 0.0499 mol) was added, followed by 14.5 g of 5% palladium on carbon. The solution was heated at reflux for three days and filtered through Celite. The solvent was removed, and the residue was purified by chromatography on silica gel with ethanol (0-20%) in dichloromethane containing 1% tdethylamine. The solvent was removed, and the residue was redissolved in dichloromethane and washed with water at pH 8. The organic layer was dried over sodium sulfate and concentrated to dryness. The resulting solid was triturated overnight in ethyl acetate. Filtration gave 9.09 g (46%) of (±)-4-((αR*)-α-((2R*, 5S*)-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N,N diethylbenzamide as a tan solid. Calc. for C24H33N3O2 0.5 H2O: C, 71.26; H, 8.47; N, 10.39. Found: C, 71.12; H, 8.47; N, 10.49. NMR (300 MHz, CDCl3): δ0.9 (d, J=6 Hz, 3H),1.2 (d and brtr, 9H); 1.5 (t, J=10 Hz, 1H); 2.2 (br m, 1H); 2.5 (m, 1H); 2.6 (d, J=9 Hz, 1H); 2.8 (m, 2H); 3.1-3.5 (br m, 5.3 (s, 1H); 6.6 (d, J=8 Hz, 1H) 6.7 (d, J=8 Hz, 1H); 6.8 (s, 1H); 7.1 (t, J=8 Hz, 1H); 7.2 and 7.3 (AB q, J=8 Hz, 4H), 9.0 (br s, 1H).

Provenance & Evidence