A Ruthenium Complex‐Catalyzed Cyclotrimerization of Halodiynes with Nitriles. Synthesis of 2‐ and 3‐Halopyridines

Eva Bednářová (1, 2) , Evelina Colacino (1) , Frédéric Lamaty (1) , Martin Kotora (2)

1 IBMM - Institut des Biomolécules Max Mousseron [Pôle Chimie Balard]
2 UK - Univerzita Karlova [Praha, Česká republika] = Charles University [Prague, Czech Republic]

Monohalo‐ and dihalodiynes efficiently undergo [2+2+2] cyclotrimerization with nitriles in the presence of a catalytic amount of the ruthenium complex Cp*RuCl(cod) (10 mol%) to afford the corresponding halopyridines under ambient conditions in good isolated yields (up to 90%). The halopyridines are formed as two separable regioisomers. This is the first example of a direct synthesis of halopyridines from haloalkynes and nitriles.

Mots clés: alkynes; cyclotrimerization; Homogeneous catalysis; nitrogen heterocycles; ruthenium

Domaines: Catalyse; Chimie organique

Eva Bednářová, Evelina Colacino, Frédéric Lamaty, Martin Kotora. A Ruthenium Complex‐Catalyzed Cyclotrimerization of Halodiynes with Nitriles. Synthesis of 2‐ and 3‐Halopyridines. Advanced Synthesis and Catalysis, 2016, 358 (12), pp.1916-1923. ⟨10.1002/adsc.201600127⟩. ⟨hal-02385428⟩