Sodium hydride → tert-butyl (3R)-3-methyl-4-[4-[4-(4-pyridyl)piperazin-1-yl]phenoxy]butyrate

Beteiligte Stoffe

Reaktionsschritte

Sodium hydride (60% dispersion in mineral oil, 2.44 g) was added to a stirred suspension of 4-[4-(4-pyridyl)piperazin-1-yl]phenol (15.5 g) in dry DMF (120 ml) and the mixture was stirred for 45 minutes at room temperature. tert-Butyl (3R)-3-methyl-4-(p-toluene-sulphonyloxy)butyrate (20 g) was added and the mixture was stirred at room temperature for 20 hours. The mixture was evaporated and the residue was partitioned between dichloromethane and water. The organic layer was washed with water, filtered through phase separating paper (Whatman IPS) and evaporated. The residue was triturated under diethyl ether. The solid so obtained was recrystallised from ethyl acetate to give tert-butyl (3R)-3-methyl-4-[4-[4-(4-pyridyl)piperazin-1-yl]phenoxy]butyrate (10.6 g), m.p. 112°-113° C.; [alpha]D =-5.5° (conc.=1 g/100 ml of methanol; 20° C.); NMR (CDCl3) δ 8.3(2H,d), 6.89(4H,m), 6.7(2H,m), 3.79(2H,d), 3.46(4H,m), 3.28(4H,m), 2.31-2.53(2H,m), 2.08.2.21(1H,m), 1.44(9H, s), 1.07(3H,d).

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