Abstract Piperonyl butoxide (PBO) 1 was prepared via the successive chloromethylation and etherification of dihydrosafrole 3. In this work, during the chloromethylation of 3, several by- products such as 5 (the isomer of chloromethyldihydrosafrole 4), 6-propylpiperonyl alcohol 6, bis (chloromethyl)-dihydrosafrole 7 and 8, bis (2-propyl-4, 5-methylenedioxyphenyl) methane 9 and di (2-propyl-4, 5-methy lene-dioxybenzyl) ether 10 were found. However, it ...
