Functionalization of 1,3,4-Oxadiazoles and 1,2,4-Triazoles via Selective Zincation or Magnesiation Using 2,2,6,6-Tetramethylpiperidyl Bases.

Kuno SchwärzerCarl Phillip TüllmannSimon GraßlBartosz GórskiCara E Brocklehurst Paul Knochel

Published in: Organic letters (2020)

We report the metalation of the 1,3,4-oxadiazole and 1,2,4-triazole scaffolds via regioselective zincation or magnesiation using the TMP bases (TMP = 2,2,6,6-tetramethylpiperidyl) TMP2Zn·2LiCl, TMP2Zn·2MgCl2·2LiCl, TMPMgCl·LiCl, and TMPZnCl·LiCl under mild conditions in THF. Subsequent trapping with various electrophiles including hydroxylamino benzoates gives access to functionalized heterocycles while tolerating many functional groups.

Keyphrases

heavy metals
quantum dots
risk assessment