Sterically hindered 1,4-disubstituted 1,2,3-triazoles were prepared from aryl azides and aryl alkynes using the CuAAC reaction. The effects of electronic properties and steric hindrance of substrates on the outcome of the synthesis were investigated. Azides were successfully prepared from anilines, while the alkyne syntheses were attempted using the Corey–Fuchs reaction, Sonogashira coupling and Bestmann–Ohira modification of the Seyferth–Gilbert homologation of aldehydes. Alkyne synthesis was relatively challenging due to the unfavorable electronic properties and steric hindrance of the substrates. Nevertheless, three sterically hindered alkynes were successfully prepared and subsequently used to synthesize three 1,4-disubstituted 1,2,3-triazoles with varying steric and electronic properties.
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