Efficient two-step access to azafluorenones and related compounds

Nada Marquise (1) , Philip J. Harford (2) , Floris Chevallier (1) , Thierry Roisnel (1) , Andrew E. H. Wheatley (2) , Philippe C. Gros (3) , Florence Mongin (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 Department of Chemistry
3 SRSMC - Structure et Réactivité des Systèmes Moléculaires Complexes

Crystals of a lithiocuprate prepared from copper(I) chloride and lithium 2,2,6,6-tetramethylpiperidide (2 equiv) were isolated and analyzed by X-ray diffraction as (TMP)2Cu(Cl)Li2*THF. The observation of this species is consistent with its having a role in deprotocupration-aroylation. Phenyl pyridyl ketones, phenyl quinolyl ketones, and phenyl thienyl ketones were prepared in tetrahydrofuran using the lithiocuprate and aroyl chorides as electrophiles. Diaryl ketones bearing a chloro group at the 2 position (of a pyridyl or phenyl group) thus synthesized were next converted through palladium-catalyzed ring closure to polycycles of the 5H-indeno[1,2-b]pyridin-5-one, 11H-indeno[1,2-b]quinolin-11-one, 9H-indeno[2,1-c]pyridin-9-one, and 8H-indeno[2,1-b]thiophen-8-one families.

Mots clés: Deprotometallation; Copper; Lithium; Heterocycle; Palladium

Domaines: Chimie inorganique

Nada Marquise, Philip J. Harford, Floris Chevallier, Thierry Roisnel, Andrew E. H. Wheatley, et al.. Efficient two-step access to azafluorenones and related compounds. Tetrahedron Letters, 2013, 54 (24), pp.3154-3157. ⟨10.1016/j.tetlet.2013.04.020⟩. ⟨hal-00871003⟩