- Diversity-Oriented Synthesis of β-Lactams and γ-Lactams by Post-Ugi Nucleophilic Cyclization: Lewis Acids as Regioselective Switch
-
Heterocyclic fused α-methylene β-lactams were successfully synthesized by a post-Ugi InIII-catalyzed intramolecular addition reaction. Switching from InCl3 to AlCl3 led to the regioselective synthesis of α,β-unsaturated γ-lactams. Moreover, replacing terminal alkynes by substituted alkynes in the Ugi adducts resulted in the exclusive formation of γ-lactams with both catalytic systems. A regioselective approach for the synthesis of heterocyclic fused α-methylene β-lactams and α,β-unsaturated γ-lactams by employing a Ugi reaction followed by InIII- or AlIII-catalyzed intramolecular nucleophilic addition is reported.
- Li, Zhenghua,Sharma, Upendra Kumar,Liu, Zhen,Sharma, Nandini,Harvey, Jeremy N.,Van Der Eycken, Erik V.
-
supporting information
p. 3957 - 3962
(2015/06/30)
-
- Efficient synthesis of new polyfunctionalized thiadiazaacenaphthylenes from imidazo[1,2-a]pyridines
-
New heterocycles containing sulfur and nitrogen with an azaindolizine moiety were synthesized. The imidazo[1,2-a]pyridine-2,5-dicarboxylates (9a, b, 10a, b) and 5-formylimidazo[1,2-a]pyridine-2-carboxylates (17a, b) treated with ethyl thioglycolate and lithium hydroxide underwent ring closure yielding the multifunctional[2,3,3]cyclazines (13) and (18). Under similar conditions, the imidazo[1,2-a]pyridinecarbaldehydes (22a, b) and (29a, b) were converted into the linearly cyclized compounds thieno[3,2-b]imidazo[1,2-a]pyridines (23, 31) and a peri annulated product thiadiazaacenaphthylene (30).
- Moreau, Emmanuel,Chezal, Jean-Michel,Dechambre, Caroline,Canitrot, Damien,Blache, Yves,Lartigue, Claire,Chavignon, Olivier,Teulade, Jean-Claude
-
-