The preparation of 4-hydroxymethylbenzocyclobutene: To a stirred solution of 1.32 g of 4-formylbenzocyclobutene in 15 mL of ethanol at room temperature is added 0.38 g of sodium borohydride. The reaction mixture is stirred for 2 h at room temperature. Ethanol is removed using a rotary evaporator and the residual material is diluted with 50 mL of water.
The aqueous mixture is extracted with ethyl acetate. The ethyl acetate layer is washed with water and with saturated sodium chloride brine and dried over anhydrous magesium sulfate. The solution is filtered and solvent is removed from the filtrate. The yield of 4-hydroxymethylbenzocyclobutene is 1.27 g (95%, m.p. 70° C. from hexanes).
