Reacción #887

Ecuación de reacción

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

sodium 4-methyl phenoxide

4-methylphenol

→

1-(4-tolyloxyl)-1,2-bis(4-bromobenzoyl)ethylene

Disolventes

THF

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrowas removed under reduced pressure
2. 2
   workup.ADDITIONThe residue was treated with water
3. 3
   Filtraciónthe solid was filtered
4. 4
   Lavadowashed with water
5. 5
   Secadodried (Na2SO4)
6. 6
   workup.DISSOLUTIONdissolved in chloroform
7. 7
   LavadoThe chloroform solution was passed through a silica column (elution with 2-5% ether in hexane)

Procedimiento

To a solution of 1,2-dibromo-1,2-di(4-bromobenzoyl) ethane (11.1 g, 0.02 mole) in 35 ml of THF was added a suspension of sodium 4-methyl phenoxide [prepared from 0.92 g (0.04 mole) Na and 4.32 g (0.04 mole) 4-methylphenol in 30 ml THF by refluxing for 4-5 hr]. The yellow mixture was refluxed for 2-3 hr (TLC followed) after which the THF was removed under reduced pressure. The residue was treated with water, and the solid was filtered, washed with water, dried (Na2SO4), and dissolved in chloroform. The chloroform solution was passed through a silica column (elution with 2-5% ether in hexane). The result was an off white crystalline solid, 4.95 g (50%), mp 137°-8° C. IR (KBr) 3087, 3035, 2868, 1687, 1646, 1587, 1572, 1557, 1502, 1399, 1364, 1194, 1068, 1009, 971, 876, 815, 772, 526. 1H NMR (CDCl3 /35° C.) 7.92 (d, 2H, J=8.8), 7.65 (d, 2H, J=8.8), 7.55 (d, 2H, J=8.8), 7.48 (d, 2H, J=8.8), 7.27 (d, 2H, J=8.3), 7.11 (d, 2H, J=8.3), 6.32 (s, 1H), 2.4 (s, 3H). 13C NMR (CDCl3 /35° C.) 189.4, 187.6, 168.4, 150.9, 136.6, 136.0, 133.4, 132.3, 131.8, 130.9, 130.3, 129.6, 129.2, 128.2, 120.6, 101.8, 20.95. MS m/e 500 (M+).

Fuente