Regioselective Pd-catalyzed direct C1- and C2-arylations of lilolidine for the access to 5,6-dihydropyrrolo[3,2,1-ij]quinoline derivatives

Abstract

The Pd-catalyzed C–H bond functionalization of lilolidine was investigated. The use of a palladium-diphosphine catalyst associated to acetate bases in DMA was found to promote the regioselective arylation at α-position of the nitrogen atom of lilolidine with a wide variety of aryl bromides. From these α-arylated lilolidines, a second arylation at the β-position gives the access to α,β-diarylated lilolidines containing two different aryl groups. The one pot access to α,β-diarylated lilolidines with two identical aryl groups is also possible by using a larger amount of aryl bromide. The synthesis of 5,6-dihydrodibenzo[a,c]pyrido[3,2,1-jk]carbazoles from lilolidine via three successive direct arylations is also described. Therefore, this methodology provides a straightforward access to several lilolidine derivatives from commercially available compounds via one, two or three C–H bond functionalization steps allowing to tune their biological properties.

Grind-and-Heat: Solvent-free Catalytic C–H and C–X Functionalization Without a Ball Mill

“…Additionally, we were able to incorporate the G&H C-H borylation of Lilolidine as part of a one-pot C-H borylation/Suzuki-Miyaura coupling sequence without purification of the intermediate (see Scheme 5b). [39] Solvent-free Suzuki-Miyaura cross-coupling…”

Grind-and-Heat: Solvent-free Catalytic C–H and C–X Functionalization Without a Ball Mill

“…Additionally, we were able to incorporate the G&H C-H borylation of Lilolidine as part of a one-pot C-H borylation/Suzuki-Miyaura coupling sequence without purification of the intermediate (see Scheme 5b). [39] Solvent-free Suzuki-Miyaura cross-coupling…”

Strategic Advances in Sequential C-Arylations of Heteroarenes

“…C2 → C3 sequential arylation was conducted on tricyclic 5,6-dihydropyrrolo­[3,2,1- ij ]­quinolines, 232 , having a similar skeletal composition to indoles (Scheme ). During optimizations, the selectivity at the C2 position was improved using 2 mol % PdCl­(C 3 H 5 )­(dppb). One equivalent of aryl bromides was reacted with 1.5 eq.…”