Amaral MF. Z. J, Baumgartner AA, Vessecchi R, Clososki GC * Universidade de São Paulo,
Ribeirão Preto, Brazil
Directed Metalation of 1-Ester-Substituted Indolizines: Base/Electrophile-Controlled
Regioselective Functionalization.
Org. Lett. 2015;
17: 238-241
Key words
metalation - magnesium - indolizines
Significance
Clososki and co-workers report a directed C–H functionalization of 1-ester-substituted
indolizines using several organometallic bases. The metalation takes place under mild
conditions, and the reaction with different electrophiles allows the synthesis of
a number of polyfunctional indolizines in good yields.
Comment
Lithium amides favor C-5 functionalization, while TMPMgCl·LiCl gives C-2 substituted
derivatives as major products by ortho metalation. The authors found that in the case of functionalization with TMPMgCl·LiCl,
the reactivity of the electrophile plays a key role in the regioselectivity of the
reaction.
