反应详情

In accordance with the statements of German Offenlegungsschrift No. 2,238,734, 4,4'-bis-(chloromethyl)biphenyl (42) is reacted with salicylaldehyde to give 4,4'-bis-(benzo[b]furan-2-yl)-biphenyl and this product is reacted further with oleum to give a mixture of the corresponding tri- and tetra-sulphonic acids. This mixture can also be used for the optical brightening of cotton and polyamide.