Synthesis , mechanism and application of Organic Name reaction.pptx

Debus-Radziszewiski Imidazole Synthesis.
Knorr- Pyrazole Synthesis.
Pinner Pyrimidine Synthesis

1. Organic name Reactions Presented By: Divya Ashok Dhule M.Pharm.(Pharmaceutical Chemistry) 1 st year Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033

2. Contents: Debus-Radziszewiski Imidazole Synthesis. Knorr- Pyrazole Synthesis. Pinner Pyrimidine Synthesis

3. Debus-Radziszewski Imidazole Synthesis: This reaction is named after Heinrich Debus & Bronislaw leonard Radziszewski. It is an organic multicomponent reaction used for the synthesis of imidazole from carbonyl , an aldehyde and ammonia . The dicarbonyl component is commonly gloyoxal but can also include various 1 ,2- diketones & ketoaldehyde . Dicarbonyl Compound Aldehyde Amine Ammonia Imidazole

4. Mechanism: The reaction occur in two stages. In first stage , the dicarbonyl and ammonia condense to give an diimide.

5. 2.Diimine condenses with aldehyde gives Imadazole. A modification of this general method where one equivalent of ammonia is replaced by an amine affords N-Substituted imidazoles in good yield. . Dimine aldehyde Imadazole Carbonyl comp. Aldehyde Ammonia1ryAmmine Imadazole

6. Application: It is the important precorsor for the synthesis of systemic antifungal agent . Imidazoles has been used extensively as corrosion inhibitor on transition metals such as copper. Imidazoles can also be used as organic structure directing agent to synthesize zeolites . Benzaldehyde 1,5-naphthalenediamine Zeolites

7. Knorr Pyrazole Synthesis: Th e Knorr pyrazole synthesis is an organic reaction used to convert a hydrazine or its derivatives and a 1,3-dicarbonyl compound to a pyrazole using an acid catalyst.

8. Mechanism:

9. Application: The important precursor for the drug tolmetin ( NSAID ) . It was also found in many drug such as atorvastatin , ketorolac & sunitinib . The reactions is utilized for the synthesis of metal chelate, photographic dyes, herbicides and biologically active compound. 4,4-Dimethoxy-2-butanone 1-n-butyl-3 &5-methylpyrazole.

10. Pinner Pyrimidine Synthesis: Introduction : Pyrimidine is in aromatic heterocyclic organic compound, six-membered heterocyclic ring with two nitrogen atom s at position 1 and 3.colourless solid, weakly basic with melting point of 225.the moiety is uses as antimalaria, antiviral, anticancer etc…. 3 Department Of Pharmaceutical Chemistry N N 1 2 3 4 5 6 IUPACName: 1,3-diazabenzene. Fig. Imidazole

11. Pinner Pyrimidine reaction is a strong acid- promoted condensation between non-N- substituted amidine and β-keto ester ( β-diketone) to form a type of nitrogenous heterocyclic moiety called pyrimidine. This reaction involves cyclization reaction of amidines with β- diketone molecule in present of acid as catalyst forming pyrimidine.the most common pyrimidine synthesis involves the combination of a 1,3-dicarbonyl component with either urea or amidines/guanidine.

12. Mechanism: Protonation. Attack by amidine Proton transfer Dehydration Proton transfer Protonation Nucleophile attack/cyclization Dehydration Deprotonation

13. Application: Pyrimidine derivatives have been prepared via this reaction procedure amidines react with 1,3- dicarbonyl compound to form 2,4,6- trisubstituted pyrimidine.

14. Amidine react with β- keto ester to provide hydroxypyrimidine .

15. References: Organic Chemistry of Natural Products Vol 1 Gurdeep R.Chatwal Edited by M. Arora. Page number 276. Gelens, E.; De Kanter, F. J. J.; Schmitz, R. F.; Sliedregt, L. A. J. M.; Van Steen, B. J.; Kruse, Chris G.; Leurs, R.; Groen, M. B.; Orru, R. V. A. (2006). “Efficient library synthesis of imidazoles using a multicomponent reaction and microwave irradiation”.p.n.242 Crouch, R. David; Howard, Jessica L.; Zile, Jennifer L.; Barker, Kathryn H. (2006). “Microwave-Mediated Synthesis of Lophine: Developing a Mechanism To Explain a Product”. J. Chem. Educ. 83 (11): 1658–1660.