Catalytic Direct-type 1,4-Addition Reactions of Alkylazaarenes.
Hirotsugu SuzukiRyo IgarashiYasuhiro YamashitaShū KobayashiPublished in: Angewandte Chemie (International ed. in English) (2017)
1,4-addition reactions of alkylazaarenes catalyzed by strong Brønsted bases have been developed for the first time. The desired reactions with α,β-unsaturated amides proceeded under mild reaction conditions to give the 1,4-adducts in high yields. Both ortho- and para-substituted azaarenes afforded the desired adducts in high yields. Regioselective reactions of di- or trimethylpyridine were found to be possible depending on the acidity of the α-hydrogen atoms. Furthermore, a candidate of allosteric protein kinase modulators was synthesized in two steps. An asymmetric variant of this reaction was also found to be feasible.