反应 #457541

反应方程式

4-chloro-6-methoxy-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one

n-BuLi

1-butyne

→

4-(1-butynyl)-6-methoxy-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one

收率 48.0%

溶剂

—

hexanes

THF

反应条件

后处理

1. 1
   其他was quenched with 20% aqueous citric acid
2. 2
   萃取The mixture was extracted with ether
3. 3
   萃取the organic extract
4. 4
   洗涤was washed with saturated aq. NaHCO3
5. 5
   浓缩The solution was concentrated under reduced pressure
6. 6
   其他the crude product was recrystallized from ethyl acetate-hexanes

实验过程

To a stirred, cooled(-78° C.) solution of 0.5 g(excess) of 1-butyne in 3 mL of anhydrous THF was added 1.6 mL(4.0 mmol) of a 2.5M solution of n-BuLi in hexanes over 3 min. The solution was stirred 5 min. and charged with 266 mg(1.00 mmol) of 4-chloro-6-methoxy-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one as a single portion. The solution was warmed to -10° C. over 20 min., whereupon it was quenched with 20% aqueous citric acid. The mixture was extracted with ether, and the organic extract was washed with saturated aq. NaHCO3 then brine. The solution was concentrated under reduced pressure, and the crude product was recrystallized from ethyl acetate-hexanes to afford 144 mg(48%) of 4-(1-butynyl)-6-methoxy-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one as a white solid, mp 161-162° C. 1H NMR(300 MHz, CDCl3) δ 8.81(br. s, 1H); 7.07(d, 1H, J=2 Hz); 6.94(dd, 1H, J=9, 2 Hz); 6.81(d, 1H, J=8 Hz); 3.82(s, 3H); 2.34(q, 2H, J=7 Hz); 1.22(t, 3H, J=7 Hz).

来源