A general synthesis of diversely substituted indazoles and hetero-aromatic derivatives from o-halo-(het)arylaldehydes or -phenones

International audienceA set of variously substituted indazoles and hetero-aromatic derivatives were synthesized from o-halo-(het)arylaldehydes using a palladium catalyzed amination followed by cyclization. Starting from phenones, this process was extended to give 3-substituted indazoles. Moreover, N-1-substituted-indazoles can be reached by this strategy using an optional selective N-1-alkylation step during the process. This methodology offers a general and easy route for the synthesis of regioselectively substituted indazoles

A Straightforward and Highly Diastereoselective Access to Functionalized Monofluorinated Cyclopropanes via a Michael Initiated Ring Closure Reaction

International audienceThe synthesis of highly functionalized monofluorinated cyclopropanes based on a Michael Initiated Ring Closure (MIRC) reaction has been developed. The addition of quaternary ammonium salts derived from ethyl bromofluoroacetate on a panel of electron deficient alkenes followed by cyclization gave rise to an efficient access to monofluorinated cyclopropanes with good yields and remarkable diastereoselectivity

A Straightforward and Highly Diastereoselective Access to Functionalized Monofluorinated Cyclopropanes <i>via</i> a Michael Initiated Ring Closure Reaction

The synthesis of highly functionalized monofluorinated cyclopropanes based on a Michael Initiated Ring Closure (MIRC) reaction has been developed. The addition of quaternary ammonium salts derived from ethyl bromofluoroacetate on a panel of electron deficient alkenes followed by cyclization gave rise to an efficient access to monofluorinated cyclopropanes with good yields and remarkable diastereoselectivity