M-Cresol → HCID 23369052, compound

Participants

Reaction Conditions

Reaction Steps

Dichlorofluorene (DCF) (35.27 g, 0.15 mole) is weighed into a powder addition funnel and dissolved in 20 mL of dry dichloromethane. Liquid m-cresol (64.88 g, 0.6 mole) is weighed into a 250 mL three-necked round-bottomed flask which is equipped with a stirrer, heating mantle, nitrogen inlet, condenser, thermometer, and drying tube. Dry dichloromethane (80 mL) is added and the mixture is heated to 40° C. with stirring. DCF solution is added slowly to the mixture as the temperature is maintained at about 40° C. The reaction is rapid as evidenced by copious production of HCl bubbles after each addition. After addition is complete, the reaction is stirred for an additional half hour and then checked by LC. The reaction is complete, and the chromatograph shows peaks for the desired bisphenol (9,9-bis(2-hydroxy-4-methylphenyl)fluorene) along with isomers. The mixture is dissolved in toluene and refluxed with 0.5 mL of methane sulfonic acid collecting water formed during the cyclization reaction in a Dean-Stark trap. The toluene is then removed by rotary evaporation and the residue is slurried with acetonitrile, chilled and filtered to yield the spiroether [3',6'-dimethylspiro[fluorene-9,9'-xanthene] as an off-white powder. The isomeric bisphenols formed in the alkylation reaction do not cyclize and remain dissolved in the acetonitrile.

Provenance & Evidence