Reacción #56382

Ecuación de reacción

7-formyl-3-methyl-octa-2,4,6-trien-1-oic acid ethyl ester

2,6-dichloro-4-methoxy-5-methyl-benzyl-triphenylphosphonium chloride

2,6-dichloro-4-methoxy-3-methyl-benzyl chloride

1,2-butylene oxide

triphenylphosphine

→

9-(2,6-dichloro-4-methoxy-5-methyl-phenyl)-3,7-dimethyl-nona-2,4,6,8-tetraen-1-oic acid ethyl ester

Disolventes

toluene hexane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONAfter the addition of 120 ml
2. 2
   Extracciónexhaustively extracted with methanol/water (60:40 parts by volume)
3. 3
   OtroThe resulting solution is evaporated under reduced pressure
4. 4
   OtroThe oily residue is purified by adsorption on silica gel
5. 5
   Lavadofor the elution

Procedimiento

100 g. of 2,6-dichloro-4-methoxy-5-methyl-benzyl-triphenylphosphonium chloride, prepared from 52 g. of 2,6-dichloro-4-methoxy-3-methyl-benzyl chloride and 57 g. of triphenylphosphine, are treated with 42 g. of 7-formyl-3-methyl-octa-2,4,6-trien-1-oic acid ethyl ester. After the addition of 120 ml. of 1,2-butylene oxide, the resulting mixture is heated to 80°-85° C. for 4 hours while stirring. The mixture is diluted with toluene/hexane (1:1 parts by volume) and exhaustively extracted with methanol/water (60:40 parts by volume). The resulting solution is evaporated under reduced pressure. The oily residue is purified by adsorption on silica gel using toluene for the elution. 9-(2,6-dichloro-4-methoxy-5-methyl-phenyl)-3,7-dimethyl-nona-2,4,6,8-tetraen-1-oic acid ethyl ester is obtained from the eluate and melts at 100°-101° C. after recrystallization from benzene/hexane (50:50 parts by volume).

Fuente