Scandium Triflate-Catalyzed Nucleophilic Additions to Indolylmethyl Meldrum’s Acid Derivatives via a Gramine-Type Fragmentation: Synthesis of Substituted Indolemethanes

Abstract

Treatment of indolylmethyl Meldrum's acids with catalytic scandium triflate and a variety of nucleophiles results in the nucleophilic displacement of the Meldrum's acid moiety via a gramine-type fragmentation. The reaction is useful for the generation of heterocyclic compounds of significant molecular complexity.

Fe(OTf)3‐Catalyzed Aromatization of Substituted 3‐Methyleneindoline and Benzo­furan Derivatives: A Selective Route to C‐3‐Alkylated Indoles and Benzofurans

“…Yus and co‐workers developed a noncatalytic C‐3 alkylation using activated benzyl alcohol through a hydrogen‐transfer strategy with an excess amount of KOH 10. Armstrong et al described a Sc(OTf) 3 ‐catalyzed nucleophilic substitution of indolylmethyl Meldrum's acids 11. Intermolecular hydroarylation of indoles with alkenes in the presence of [(PPh 3 )AuCl]/AgOTf12a and with alkynes in the presence of ruthenium complexes/TFA12b have also been demonstrated.…”

Design, synthesis, and molecular docking of new 5-HT reuptake inhibitors based on modified 1,2-dihydrocyclopenta[b]indol-3(4H)-one scaffold

“…The mixture was stirred for 18 h at 30 • C. After completion of the reaction, the solvent was removed under reduced pressure and the residue was purified with flash chromatography, (EtOAc/Hex, 1:2). 25 : Yellow oil, yield 48%, 26 : Yellow oil, yield 50%, 1…”

Sulfonyl Azoles in the Synthesis of 3-Functionalized Azole Derivatives

“…Using a related approach, sulfonyl indazoles and sulfonyl pyrroles can be prepared and used by exploiting the same reactivity portrayed in Scheme for sulfonyl indoles. Few examples of other leaving groups, such as Meldrum's acid and barbituric acid, in precursors of type 3 , have been reported in the literature 18. However, these compounds have not yet found widespread utilization in synthesis.…”