In(OTf)₃-Catalyzed One-Pot Tandem Mannich and Conia-Ene Cyclization Reaction of N-Propargyl Amido Alcohols with 1,3-Dicarbonyl Compounds: An Approach To Construct Tetrahydro-1H-pyrrolo[2,1-a]isoindolone-1,1-dicarboxylate and Its Application

Abstract

A one-pot tandem reaction has been developed for the synthesis of substituted tetrahydropyrroloisoindolone via Mannich reaction of N-propargyl amido alcohols with 1,3-dicarbonyl compounds followed by Conia-ene cyclization reaction in moderate to good yields catalyzed by indium­(III)­triflate [In­(OTf)3]. The reaction is highly regioselective with an exo-cyclic double bond in the pyrrolidine ring. The substituted tetrahydropyrroloisoindolone can be converted to 5H-pyrrolo­[2,1-a]­isoindol-5-one via decarboxylative aromatization reaction.

Novel Oleanolic Acid-Phtalimidines Tethered 1,2,3 Triazole Hybrids as Promising Antibacterial Agents: Design, Synthesis, In Vitro Experiments and In Silico Docking Studies

“…Wishing to study the effect of the presence of a hydroxy and or acetoxy group on the antibacterial activity of our molecules, we subsequently prepared the hydroxylactams 7a and 7e, as well as the acetoxylactam 8g . In this sense, the selective reduction of propargylatedisoindolinones 6a and 6e was performed by using excess of NaBH 4 (4 equiv) in a dry MeOH at 0 °C [ 78 ] leading to the hydroxylactams 7a and 7e in 95% and 50% isolated yields, respectively ( Scheme 2 ). Using our recently reported one-pot reduction–acetylation protocol, imide 6g afforded the α-acetoxy-lactam 8g in a 98% overall yield ( Scheme 2 ) [ 79 ].…”

Cyclization Strategies Using Imide Derivatives for the Synthesis of Polycyclic Nitrogen‐Containing Compounds

“…Then, the adduct 14 undergoes an intramolecular Conia-ene reaction via 15 to afford intermediate 16, which is protodemetallated to produce tricycle 17. This protocol was demonstrated for 22 examples, produced in a range of 30-90 % yields [21] (Scheme 3b).…”

Cascade 1,3-Dipolar Cycloaddition and Lactamization for Diastereoselective Synthesis of Pyrrolidinedione-Fused Tetrahydropyrroloisoindolones

“…The Saikia group developed a method for stereoselective synthesis of substituted pyrroloisoindolone via aza-Prins cyclization of 3-hydroxy-2-(4-phenylbut-3-yn-1-yl)-isoindolin-1-one through endocyclic N -acyliminium ions (Scheme D) . They also developed an In­(III) triflate-catalyzed Mannich and Conia-Ene cyclization of N -propargyl amido alcohols with 1,3-dicarbonyl compounds in a one-pot fashion (Scheme E) …”

“…10 They also developed an In(III) triflate-catalyzed Mannich and Conia-Ene cyclization of N-propargyl amido alcohols with 1,3-dicarbonyl compounds in a one-pot fashion (Scheme 1E). 11 For the synthesis of pyrrolidinedione-fused tetrahydro-5Hpyrrolo[2,1-a]isoindol-5-one scaffold, the Grigg group intro-duced a two-step synthesis involving [3 + 2] cycloaddition and Pd-catalyzed carbonylative cyclization (Scheme 2A). 12 Toxic TI(AcO) 2 was used to promote carbonylative cyclization.…”