Reacción #889

Ecuación de reacción

KBr

1,2-dibromo-1,2-di(4-bromobenzoyl) ethane

sodium methoxide

→

1,2-Bis(4-bromobenzoyl)-1-methoxyethane

Disolventes

methanol

methanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe yellow brown mixture was refluxed for 1-1.5 hr
2. 2
   OtroThe solvent was removed by distillation
3. 3
   Extracciónthe mixture was extracted with 100 mL chloroform
4. 4
   ExtracciónThe chloroform extract
5. 5
   Lavadowas washed with water
6. 6
   Secadodried (Na2SO4)
7. 7
   Concentraciónconcentrated
8. 8
   OtroThe residue obtained
9. 9
   Otroto yield off-white crystalline solid, 6.6 g (78%), mp 153°-154° C

Procedimiento

To a solution of 1,2-dibromo-1,2-di(4-bromobenzoyl) ethane (11.1 g, 0.02 mole) in 150 mL dry methanol was added a solution of sodium methoxide in methanol (0.92 g sodium in 50 mL methanol). The yellow brown mixture was refluxed for 1-1.5 hr. The solvent was removed by distillation, the residue was suspended in water and the mixture was extracted with 100 mL chloroform. The chloroform extract was washed with water, dried (Na2SO4) and concentrated. The residue obtained was titrated with dry methanol-ether (3:1) to yield off-white crystalline solid, 6.6 g (78%), mp 153°-154° C. IR (KBr): 3106, 3062, 2932, 1689, 1649, 1583, 1556, 1403, 1223, 1202, 1182, 1086, 1010, 1000, 857, 814, 738, 618, 472 cm-1. 1H (DMSO-d6 /40° C.): 7.95 (d, 2H, J=7.8), 7.77 (4H, J=8.8), 7.72 (d, 2H, J=7.8), 6.89 (s, 1H), 4.03 (s, 3H). 13C (DMSO-d6 /40° C.): 189.9, 187.2, 168.8, 139.9, 135.9, 133.1, 132.2, 131.8, 130.3, 128.1, 127.4, 98.6, 58.5. MS m/e 424 (M+).

Fuente