General methodology for the chemoselective N-alkylation of (2, 2, 6, 6)-tetramethylpiperidin-4-ol: Contribution of microwave irradiation. Issue 3 (17th January 2019)

• Record Type: Journal Article
• Authors: Membrat, Romain; Vasseur, Alexandre; Giordano, Laurent; Martinez, Alexandre; Nuel, Didier
• Is Part Of: Tetrahedron letters. Volume 60:Issue 3(2019)
• Page Start: 240
• Page End: 243
• Publication Date: 2019-01-17
• Subjects: Chemoselective alkylation -- Functional tolerance -- Microwave assisted reactions -- Sterically hindered amines; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2018.12.020
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Highlights: Alkylation of sterically hindered amines. N -Alkylation versus O -Alkylation. Microwave irradiation used to decrease reaction time. Microwave irradiation improves the yields. Abstract: A convenient method to access a broad variety of N -alkyl-(2, 2, 6, 6)-tetramethylpiperidin-4-ol compounds is reported. The thermal treatment of a mixture of (2, 2, 6, 6)-tetramethylpiperidin-4-ol and allyl or benzyl bromide derivatives gave the corresponding N –alkylated compounds in good yields while leaving the hydroxyl functional group intact. Whereas 40 h were needed to reach complete conversion, microwave irradiation allowed the reaction time to be reduced (20 min) and improved the yields in most cases.