Details

Autor(en) / Beteiligte

• Srinivasan, Ramasamy
• Dey, Aniruddha
• Nagarajan, N Shanmugam
• Kumaran, Rajendran Senthil
• Gandhi, Thirumanavelan
• Maiti, Debabrata

Titel

Pd-Catalyzed C-H arylation of pyridazine-based fused 1,2,4-triazoles: overriding selectivity at the usual position by undermining of preferred chelate formation

Ist Teil von

• Chemical communications (Cambridge, England), 2017-10, Vol.53 (85), p.11709-11712

Ort / Verlag

England

Erscheinungsjahr

2017

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The applicability of C-H functionalization to medicinally important 2-pyridyl-based N-heterocycles suffers from severe challenges owing to the high Lewis basicity of the N-atom. This arrests catalytic activity and yields undesirable positional selectivity due to preferential chelate formation. In this regard, we report a novel palladium(ii)-catalyzed arylation strategy on multiple-N-containing pyridazines by over-riding the functionalization due to a chelated palladacycle. We report a regioselective mono-arylation at the 8-position of diphenyl azolopyridazines without any ortho-C-H activation on the proximal phenyl groups. This methodology presents a broad arylation scope with uncompromised yield and positional selectivity, including the heteroarylation of N-heterocycles, which is an unprecedented feat for these types of molecules.