Synthesis and characterization of new 1,3-benzodioxole derivatives based on Suzuki-Miyaura coupling reaction

In this work, new heterocyclic compound derivatives of 1,3-benzodioxole 6a-s have been prepared in good yields (33-89%). This work included using (6bromobenzo[d][1,3]dioxol-5-yl)methanol (1) as a starting material in the synthetic route. Appel conditions (CBr4/PPh3, DCM) were applied on 1, which provided compound 2 in an excellent yield (91%). Nucleophilic substitution of 2 with NaN3 in MeOH gave 5-(azidomethyl)-6-bromobenzo[d][1,3] dioxole (3) in a very good yield (88%). Subsequent Huisgen 1,3-dipolar cycloaddition reaction (click-reaction) between 3 and phenylacetylene in the presence of CuI as a catalyst afforded only single 1,4-regioisomer of 1-((6bromobenzo[d][1,3]dioxol-5-yl)methyl)-4-phenyl-1H1,2,3-triazole (4) in 82% yield. Followed by SuzukiMiyaura coupling reaction of 4 with different substituents of boronic acid 5a-s in the presence of PdCl2(PPh3)2 as a catalyst, PPh3 as a ligand and K2CO3 as base furnished the desired products 6a-s.