Enantioselective Catalytic Dearomative Addition of Grignard Reagents to 4-Methoxypyridinium Ions
作者:Yafei Guo、Marta Castiñeira Reis、Johanan Kootstra、Syuzanna R. Harutyunyan
DOI:10.1021/acscatal.1c01544
日期:2021.7.16
We describe a general catalytic methodology for the enantioselective dearomative alkylation of pyridine derivatives with Grignard reagents, allowing direct access to nearly enantiopure chiral dihydro-4-pyridones with yields up to 98%. The methodology involves dearomatization of in situ-formed N-acylpyridinium salts, employing alkyl organomagnesium reagents as nucleophiles and a chiral copper (I) complex
Catalytic Enantioselective Addition of Dialkylzinc Reagents to<i>N</i>-Acylpyridinium Salts
作者:M.â Ãngeles Fernández-Ibáñez、Beatriz Maciá、Mariaâ Gabriella Pizzuti、Adriaanâ J. Minnaard、Benâ L. Feringa
DOI:10.1002/anie.200904981
日期:2009.11.23
A pinch of salt: The first catalyticaddition of dialkylzincreagents to N‐acylpyridinium salts with good yields and excellent enantioselectivities uses a copper–(S)‐L complex as the catalyst. The versatility of the method is illustrated in the formal synthesis of the alkaloid (R)‐coniine. Bn=benzyl, Tf=trifluoromethanesulfonyl.