Abstract

Under Mitsunobu conditions N-Boc-2-(hydroxymethyl)piperidine acts as a source of tert-butyl residue for the conversion of phenols into aryl tert-butyl ethers under neutral conditions. This reactivity can be attributed to a neighboring group contribution which strongly depends on the structure of the employed N-Boc-aminoalcohol. Five other, closely related N-Boc-aminoalcohols investigated here did not show this special reactivity, and gave the regular Mitsunobu coupling products.

Keywords: N-Boc-aminoalcohols, tert-butyl ether, Mitsunobu reaction, neighboring group contribution, protecting group, stereoselective reaction, contaminant, neutral, triphosgene