ammonium hydroxide; sodium acetate in tetrahydrofuran; water diazotized p-aminophenyldimesitylborane/THF added slowly to chilled THF/H2O soln. of benzenesulfonamide derivative and excess sodium acetate; ammonium hydroxide addn.; extn. with ethyl ether and water; evapn. of org. layer;

decompn. at high temp.; 60/40 mixture of p-chlorophenyldimesitylborane/phenyldimesitylborane;