4,5-Dichlorophthalic acid → (4,5-Dichloro-1,2-phenylene)dimethanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 1.24 g portion of 4,5-dichlorophthalic acid is dissolved in 40 mL anhydrous tetahydrofuran and the solution is cooled to 0° C. To this solution is slowly added 4 mL of borane-methyl sulfide. The reaction flask is first warmed to room temperature, then heated to reflux for 12 hours. The product mixture is cooled to 0° C., then slowly quenched with 50 mL methyl alcohol. Following removal of the solvent, the residue is partitioned between 40 mL water, and 100 mL 1:1 ethyl acetate tetrahydrofuran. The organic layer is washed with 30 mL brine, then dried over magnesium sulfate. Purification by silica gel chromatography (2:1 ethyl acetate/hexane) affords 1.01 g of the desired product as a white solid, m.p. 128°-136° C. MS(Hi res): m/z Calcd for C8H8Cl2O2 205.9901 Found 205.9872

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