2. The Ugi reaction is a multi-component reaction in organic chemistry involving a ketone or aldehyde, an amine
an isocyanides and a carboxylic acid to form a bis-amide or α-N-acylamino amide. The reaction is named after Ivar
Karl Ugi, who first reported this reaction in 1959
General Reaction
7. This is a three-component reaction between a carboxylic acid, a carbonyl compound such as a ketone or
aldehyde, and an isocyanide, offers direct access to α-acyloxy carboxamides.
General Reaction
8. L. Banfi, R. Riva, Organic reactions ( A. B. Charette, Ed.). John Wiley & Sons, Inc.,
Hoboken, NJ, 2005, Vol. 65, pp. 1–140. The Passerini reaction. 2005, 1-140.
Mechanism
9. Acid isosteres in Passerini Reaction
• HN3 and Al(N3)3---------- alpha hydroxy tetrazoles
• TMSN3 -------------------- CIS constrained norstatine analogue
• Silanol--------------------- α-siloxyamides
• sulfinic acid --------------- α-(sulfonyloxy)amides
• Phosphinic acids----------- phosphinyloxy amide
Green Chem. 2016, 18, 3718-3721.
Org. Lett. 2010, 12, 4341-4343.
Synthesis of Pharmaceutically relevant compounds
10. Carbonyl isosteres in Passerini Reaction
• Acylphosphonate --------------- α-amidophosphates
• Alcohols ------------------------- α-acyloxy carboxamide
• Isatins ---------------------------- oxindole derivatives
T. Ngouansavanh, J. P. Zhu, Angew. Chem. Int. Edit.
2006, 45, 3495-3497
T. Kaicharla, S. R. Yetra, T. Roy, A. T. Biju, Green
Chem. 2013, 15, 1608-1614.
Synthesis of Pharmaceutically relevant compounds
11. Passerini reaction in formation of 2,4,5-trisubstituted oxazoles.
caspase 3/7 activators via Passerini reaction
M. Salah Ayoup et al. Eur.J. Med. Chem. 168 (2019) 340-356
L. Wang, Z. L. Ren, M. Chen, M. W. Ding, Synlett 2014, 25, 721-723
Synthesis of Pharmaceutically relevant compounds
13. One pot acid catalyzed
cyclocondensation reaction of β-keto
ester, an aldehyde and urea that forms
3,4-dihydropyrimidin-2(H)-ones
(DHPMs)
Biginelli reaction
16. Asymmetric Biginelli reaction
Eur J Org Chem 2010:3802–3805
The DHPMs are in general obtained as racemic mixtures. However,
it is the chiral DHPMs that are important in a wide range of
pharmacological functions such as calcium channel blocker,
antihypertensive activity, anticancer activity, anti-inflammatory
activity.
17. Org. Lett. 2021, 23, 2699−2703
• The couplings are performed in a planetary ball mill
• Under solvent-free conditions.
• Acetic acid or ytterbium triflate are used as catalysts
Biginelli reaction: Recent Advances
18. Biginelli reaction: Modifications
Atwal Modification (1987)
• Two step process
• Useful in case of poor yielding aliphatic aldehydes and aldehydes having hindered carbonyl function due to ortho-
substituents
• First step: separate synthesis of unsaturated ketoester via Knoevenagel condensation
• Second step: base catalyzed addition of substituted ureas
19. Biginelli reaction: Modifications
J. Heterocycl. Chem., 2005, 42, 703-705
Lett. Org. Chem., 2009, 6, 557-559
Replacing the urea with 5-amino-1,2,4-triazole
Modification at active methylene group:
21. Biginelli reaction: Green Perspective
J. Comb. Chem. 2005, 7, 574–583
1. Microwave Irradiation:
2. Using water as solvent:
Catal. Lett., 2009, 131, 469-473
22. Biginelli reaction: Green Perspective
3. Using ionic liquid as solvent:
4. Solvent free reaction:
Chinese J. Chem., 2005, 23, 91-97
Tetrahedron Lett., 2010, 51, 6436-6438
23. APPLICATIONS
Passerini adducts formation
E. El Mamouni, A. Dos Santos, L. El Kaim, H. Ilitki, Synlett 2016, 27, 2571-2574.
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Synthesis of Pharmaceutically relevant compounds