Novel compounds of the formula ##STR1## and processes for their preparation are described. X represents bromine or iodine and R.sub.1, R.sub.2 and R.sub.3 have the meaning indicated in the patent claim. The compounds (I) are valuable intermediates for the preparation of fluorescent brighteners of the divinylstilbene type.
本发明涉及一种新的化合物,其
化学式为##STR1##,以及其制备方法。其中X代表
溴或
碘,R.sub.1、R.sub.2和R.sub.3具有专利要求中所指定的含义。化合物(I)是制备二
乙烯基仲
芳烃型
荧光增白剂的有价值的中间体。