반응 #54531
ord-7556692fc255402b9f7f0dc2724696b2
반응 방정식
시약
용매
반응 조건
후처리
- 1기타at -50° to -70°
- 2농축The mixture was concentrated in vacuo at 30° to a small volume, ice-water
- 3workup.ADDITIONwas added
- 4추출solid NaCl and extracted with ethyl acetate (5×100 ml)
- 5건조The extract was dried (MgSO4)
- 6기타evaporated
- 7기타to give 0.657 g
- 8추출The aqueous was extracted again with CHCl3 (4×100 ml.)
- 9기타to give 0.561 g
- 10추출The last extraction
- 11기타to give 0.3 g
- 12기타The three crops were crystallized from benzene
- 13기타to give 0.548 g
실험 절차
A solution of boron tribromide (7.52 g.; 0.03 mole) in 20 ml. of CH2Cl2 was added to a solution of trans-N-[2-(dimethylamino)cyclohexyl]-3-methoxy-4-nitrobenzamide (1.93 g.; 0.006 mole) in 50 ml. of CH2Cl3 keeping the temperature at -50° to -70°. It was allowed to warm to room temperature and stirred overnight. The mixture was concentrated in vacuo at 30° to a small volume, ice-water was added followed by solid NaHCO3 to pH 8, then solid NaCl and extracted with ethyl acetate (5×100 ml). The extract was dried (MgSO4) and evaporated to give 0.657 g. of solid. The aqueous was extracted again with CHCl3 (4×100 ml.) to give 0.561 g. of solid. The last extraction was repeated to give 0.3 g. of solid. The three crops were crystallized from benzene to give 0.548 g. of orange prisms, m.p. 139°- 140°. The analytical sample melted at 138°-140° (efferv.). NMR analysis showed this product to contain ca. 30% of benzene. This impure titled product was heated at 120°-125° for 17 hours in a sublimation tube (the m.p. changed to 198°-199.5°) and was then sublimed at 170°-175° for 18 hours. The sublimate, orange prisms, melted at 202°-203.5°. uv λmax 238 nm nm (ε 11,600); 278 (7,900); 358 (2,350); 422 (2,850). ir NH/=CH/N+H/OH 3220, 3180, 3020, ~2900 broad, C=O 1655; C=C 1600; amide II/NO2 /C=C 1580, 1485, 1335; C--N/C--O 1260, 1240, 1220, 1155, 995. NMR in CDCl3 +d6DMSO (100 MHz) showed absence of benzene. Mass spectrum M+ 307.