Regioselective and Transition-Metal-Free Addition of tert-Butyl Magnesium Reagents to Pyridine Derivatives: A Convenient Method for the Synthesis of 3-Substituted 4-tert-Butylpyridine Derivatives

Rappenglück, Sebastian; Niessen, Karin V.; Seeger, Thomas; Worek, Franz; Thiermann, Horst und Wanner, Klaus T. (2017): Regioselective and Transition-Metal-Free Addition of tert-Butyl Magnesium Reagents to Pyridine Derivatives: A Convenient Method for the Synthesis of 3-Substituted 4-tert-Butylpyridine Derivatives. In: Synthesis-Stuttgart, Vol. 49, No. 17: pp. 4055-4064

Abstract

A variety of 3,4-disubstituted pyridine derivatives with a tertbutyl group in the 4-position were synthesized in a transition-metal-free, two-step reaction sequence from 3-substituted pyridine precursors. Highly regioselective addition of t-Bu2Mg to TIPS-activated pyridines and an efficient microwave-assisted aromatization with sulfur as oxidant afforded the desired 3,4-disubstituted pyridine derivatives in moderate to excellent yields. The method is compatible with many functional groups such as ester, amide, halide, nitrile or alkyne groups present in the 3-position.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Pharmacy
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0039-7881
• Language: English