P4O10/TfOH mediated domino condensation–cyclization of amines with diacids: a route to indolizidine alkaloids under catalyst- and solvent-free conditions

RSC Advances
2022.0

Abstract

A domino condensation-cyclization method is developed to synthesize indolizidine alkaloids using a P4O10/TfOH reagent system without the employment of either a catalyst or solvent. The use of a few aliphatic and aromatic dicarboxylic acids is shown along with various primary amines. This method is suitable for synthesizing pyrrolo[2,1-a]isoquinolines, pyrido[2,1-a]isoquinolines, and isoindolo[1,2-a]isoquinolinones in excellent yields. When phthalic acid is used, a workup with either NaBH4 or a saturated NaHCO3 solution provided 12b-H or 12b-OH isoindolo[1,2-a]isoquinolinones, respectively.

Knowledge Graph

Similar Paper

P<sub>4</sub>O<sub>10</sub>/TfOH mediated domino condensation–cyclization of amines with diacids: a route to indolizidine alkaloids under catalyst- and solvent-free conditions
RSC Advances 2022.0
Activating Imides with Triflic Acid: A General Intramolecular Aldol Condensation Strategy Toward Indolizidine, Quinolizidine, and Valmerin Alkaloids
Organic Letters 2020.0
One‐pot Synthesis of 2‐Aminoindole through SET Oxidative Cyclization: Concise Synthesis of Tryptanthrin and Phaitanthrin E
Chemistry – A European Journal 2023.0
Synthesis of indolo[2,1‐a]isoquinolines by <scp>CF<sub>3</sub>COOH</scp>‐induced cyclization
Journal of Heterocyclic Chemistry 2020.0
Synthesis of Pentahydroxylated Pyrrolizidines and Indolizidines
The Journal of Organic Chemistry 2009.0
Biomimetic Domino Knoevenagel/Cycloisomerization Strategy for the Synthesis of Citridone A and Derivatives
The Journal of Organic Chemistry 2021.0
Synthesis of Indole Alkaloid Analogues:  Novel Domino Stereoselective Electrophile Addition−Cyclizations of Tryptophan-Derived α-Amino Nitriles
The Journal of Organic Chemistry 2007.0
Synthesis of 4-Vinyl-1,2,3,4-tetrahydroisoquinoline from N-Tethered Benzyl-Alkenol Catalyzed by Indium(III) Chloride: Formal Synthesis of (±)-Isocyclocelabenzine
Synthesis 2020.0
Improved Total Synthesis of Indolizidine and Quinolizidine Alkaloids via Nickel-Catalyzed (4 + 2) Cycloaddition
The Journal of Organic Chemistry 2022.0
One-pot tandem route to fused indolizidines and quinolizidines: Application in the synthesis of alkaloids and bioactive compounds
Chinese Chemical Letters 2021.0