Solvent-free synthesis of propargylamines: an overview

Abstract

Propargylamines are a class of compounds with many pharmaceutical and biological properties. A green approach to synthesize such compounds is very relevant. This review aims to describe the solvent-free synthetic approaches towards propargylamines via A³ and KA² coupling reactions covering the literature up to 2021.

Fig. 1. Some drug molecules containing propargylamine backbone.

Fig. 2. Some of the important molecules synthesized from propargylamines.

Scheme 1. General mechanism for propargylamine synthesis.

Scheme 2. Cu–Ru catalyzed propagylamine synthesis.

Scheme 3. Synthesis of propargylamines catalyzed by silica-CHDA-Cu.

Scheme 4. Synthesis of fluorinated propargylamines.

Scheme 5. Synthesis of propargylamines catalyzed by Cu^I-zeolite catalyst.

Scheme 6. Proposed mechanism of multicomponent reaction catalyzed by Cu^I-USY (reproduced with permission from ref. 49).

Scheme 7. Synthesis of propargylamines via multicomponent acetylene-Mannich reaction by using impregnated copper on magnetite as catalyst.

Scheme 8. Synthesis of propargylamines catalyzed by CuNPs/TiO₂.

Scheme 9. Synthesis of propargylamines via KA² coupling.

Scheme 10. Synthesis of propargyalmines catalyzed by eggshell-supported-Cu(ii) salophen complex.

Scheme 11. Cu/HM catalyzed synthesis of tetrasubstituted propargylamines via KA² coupling.

Scheme 12. CuO/Fe₂O₃ catalyzed synthesis of trisubstituted propargylamines via decarboxylative A³ coupling reaction.

Scheme 13. CuO/Fe₂O₃ catalyzed synthesis of trisubstituted propargylamines via decarboxylative KA² coupling reaction.

Scheme 14. Synthesis of propargylamines via KA² coupling catalyzed by CuI supported Amberlyst A-21.

Scheme 15. Synthesis of propargylamines catalyzed by CuI/HTNT-5.

Scheme 16. Synthesis of propargylamines catalyzed by Cu(ii)-imine ligand@SiO₂@Fe₃O₄.

Scheme 17. Synthesis of propargylamines by A³ coupling catalyzed by FMNC.

Scheme 18. Synthesis of propargylamines catalyzed by Cu/ZnO/Al₂O₃ nanocatalyst.

Scheme 19. Synthesis of propargylamines via A³ coupling catalyzed by PS–PEG–BPy–CuBr₂.

Scheme 20. Copper-catalyzed synthesis of propargylamines via KA² coupling.

Scheme 21. Synthesis of propargylamines via KA² coupling catalyzed by Cu dopped ZIF-8.

Scheme 22. Synthesis of propargylamines catalyzed by Fe₃O₄@CuSiO₃ catalyst.

Scheme 23. Synthesis of propargylamines by A³ coupling.

Scheme 24. Propargylamine synthesis catalyzed by ZnO nanoparticles.

Scheme 25. Synthesis of propargylamines catalyzed by Zn(OTf)₂.

Scheme 26. Synthesis of propargylamines in the presence of Zn^II/HAP/Fe₃O₄ under solvent-free conditions.

Scheme 27. [Zn(l-proline)₂] catalyzed synthesis of propargylamines.

Scheme 28. Synthesis of propargylamines catalyzed by ZnCl₂–TiO₂ NPs.

Scheme 29. A tentative mechanism for the synthesis of propargylamine catalyzed by ZnCl₂–TiO₂ nanoparticles (NPs) (reproduced with permission from ref. 71).

Scheme 30. Synthesis of propargylamines containing quaternary carbon center catalyzed by AuBr₃.

Scheme 31. Catalytic synthesis of proparglymines via three-component addition reaction.

Scheme 32. Plausible mechanism of synthesis of propargylamines (reproduced with permission from ref. 73).

Scheme 33. Nickel catalyzed synthesis of propargylamines via three component coupling.

Scheme 34. Synthesis of propargylamines catalyzed by MnCl₂.

Scheme 35. Synthesis of propargylamines using silica-xerogel-supported indium(iii) composite (In/SiO₂) under conventional method.

Scheme 36. Synthesis of propargylamine using silica-xerogel-supported indium(iii) composite (In/SiO₂) under microwave assisted method.

Scheme 37. MIL-101(Cr)–SO₃Ag catalyzed synthesis of propargylamines.

Scheme 38. Synthesis of propargylamines catalyzed by Pd–Cu NWs.

Scheme 39. Plausible mechanism of A³ coupling reaction catalyzed by Pd–Cu NWs (reproduced with permission from ref. 78).

Scheme 40. Synthesis of chiral propargylamines.

Scheme 41. Synthesis of propargylamines via A³ coupling catalyzed by SnCl₂.

Scheme 42. Diastereoselective synthesis of propargylamines.

Scheme 43. Silica-immobilized NHC–Cu^I complex catalyzed propargylamine synthesis.

Scheme 44. Propargylamine synthesis catalyzed by PS–NHC–Ag(i).

Scheme 45. Propargylamines synthesis catalyzed by LiOTf.

Scheme 46. Synthesis of propargylamines catalyzed by Cu–Ni bimetallic catalyst.

Scheme 47. Synthesis of propargylamines catalyzed by CNT–Fe₃O₄–fibroin–Ag under solvent-free conditions.

Scheme 48. Synthesis of propargylamines by decarboxylative A³ coupling under metal and solvent-free conditions.

Scheme 49. LAIL@MNP catalyzed synthesis of propargylamines.

Ravi Manujyothi

Thaipparambil Aneeja

Gopinathan Anilkumar