[CH3:1][O:2][C:3](=O)C=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C([Li])CCC.[Cl:30][C:31]1[C:38]([Cl:39])=[CH:37][CH:36]=[CH:35][C:32]=1[CH:33]=O>CCCCCC.C1COCC1>[Cl:39][C:38]1[CH:37]=[CH:36][CH:35]=[C:32]([CH:33]=[CH:1][O:2][CH3:3])[C:31]=1[Cl:30]
Into a flask under argon containing 700 ml of dry THF was placed 159 g (0.47 mole) of methyl(triphenylphosphoranylidene)acetate. To the stirred suspension cooled in an ice/water bath was added dropwise 320 ml (0.47 mole) of 1.45M n-butyllithium in hexane. After stirring for 20 min, 74 g (0.42 mole) of 2,3-dichlorobenzaldehyde in 700 ml of dry THF was added. After 2 hr the reaction mixture was washed with an ammonium chloride solution, brine and dried (MgSO4). The solvent was evaporated in vacuo. The residue was taken up in ether, the undissolved solid was filtered off, and the solvent was evaporated in vacuo. The residue was distilled in a Kugelrohr apparatus at 0.005 mm Hg and the fraction distilling between 80°-100° C. collected. The distillate was distilled at 0.005 mm Hg using a Vigro column and the product collected between 101°-116° C. A preparative hplc on silica gel using hexane as the elutant gave 28.02 g of the title compound as an oil (33%).
Loading…
