1193-59-5Relevant articles and documents
Lithiation of Heterocycles Directed by α-Amino Alkoxides
Comins, Daniel L.,Killpack, Michael O.
, p. 104 - 109 (1987)
The addition of heterocyclic aromatic aldehydes to certain lithium dialkylamides gave α-amino alkoxides that were ring-lithiated with butyllithium.Alkylation and hydrolysis provided ring-substituted heterocyclic aromatic aldehydes via a one-pot reaction.The metalation of α-amino alkoxides derived from thiophenecarboxaldehydes, furaldehydes, N-methylpyrrolecarboxaldehydes, and indolecarboxaldehydes was examined.The regioselectivity of the lithiation, was dependent on the heterocycle, the amine component of the α-amino alkoxide, and the metalation conditions.A novel N-methyl metalation of α-amino alkoxides derived from N-methylpyrrole-2-carboxaldehyde and N-methylindole-2-carboxaldehyde was achieved when N,N,N'-trimethylethylenediamine was used as the amine component for in situ formation of the α-amino alkoxides.The novel directed N-methyl lithiations are attributed to an intramolecular TMEDA-like assisted metalation.
Copper-Catalyzed Three-Component Formal [3 + 1 + 2] Benzannulation for Carbazole and Indole Synthesis
Guo, Tenglong,Han, Li,Wang, Tingpeng,Lei, Lan,Zhang, Jian,Xu, Dezhu
, p. 9117 - 9128 (2020/08/14)
Three-component formal [3 + 1 + 2] benzannulation reactions of indole-3-carbaldehydes or 1-methyl-pyrrole-2-carbaldehydes with two different molecules of saturated ketones have been successfully developed under Cu-catalyzed and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated conditions. Various unsymmetrically substituted carbazoles and indoles were obtained up to 95% yield. Furthermore, the resulting products exhibit unusual aggregation-induced emission (AIE) properties in the solid state. This method features high atom-economy, cheap catalysts and oxidants, wide substrate scope, and saturated ketones as one-carbon and two-carbon sources, thus providing an efficient approach to polycyclic carbazole and indole compounds.
Palladium-catalyzed C-H formylation of electron-rich heteroarenes through radical dichloromethylation
Bao, Yan,Wang, Jian-Yong,Zhang, Ya-Xuan,Li, Yan,Wang, Xi-Sheng
supporting information, p. 3147 - 3150 (2018/07/13)
A novel palladium-catalyzed C-H formylation of electron-rich N-, O-, and S-containing heteroarenes has been developed. The key to success is that the commercially available BrCHCl2 was used as a stoichiometric carbonyl source. Mechanistic investigations indicated that different from the known Reimer-Tiemann reaction, this net C-H formylation proceeded through an electrophilc radical-type path.
