Beschreibung:
<jats:p>In 1967 Pedersen described dibenzo-18-crown-6 (1) [1]. We report the preparation of its isomeric dihydroxy derivatives 2c and 3c. Nitration of 1 in acetic acid and chloroform yields the dinitro compounds 2a and 3a. 2a and 3a have different solubility in ethylene glycol monomethyl ether and can be separated [4]. Catalytic reduction of the dinitro derivatives with hydrazine and Raney nickel leads to the diamines 2b and 3b. The diazonium salts of 2b and 3 b are heated in dilute sulfuric acid and yield the phenols 2c and 3c.</jats:p>