Presentations on Nazarov Cyclization Reaction

Recent Advances on Nazarov Cyclization PPT. Examples of asymmetric Nazarov Cyclization are covered in this slide. To Know more visit - https://chemistry-name-reaction.com/

1. Avishek Das ( 1810204 ) PhD Student Department of Chemistry IISER Bhopal Recent Advances on Nazarov Cyclizations https://chemistry-name-reaction.com/ To know more visit -

2. Outline Introduction Asymmetric Nazarov Cyclizations Chiral Auxiliary Lewis Acid Catalysis Organocatalysis

3. 4 p conrotatory electrocyclization Efficient tool to access cyclopentenones with excellent stereochemical control Various techniques ( Chiral auxiliary approach,Organocatalysis etc.) have been developed to achieve enantioselectivity Earliest Catalytic Asymmetric 4 p Electrocyclization Ivan Nazarov 3 Nazarov Cyclization - An Overview

4. Jones and co-workers J. Am. Chem. Soc. 1982 , 104 , 2642 4 Asymmetric Nazarov with a Silicon Chiral Auxiliary Stereochemical Model

5. 5 Asymmetric Nazarov with Chiral Auxiliary on the Allene Tius and co-workers Org. Lett. 2000 , 2 , 2447

6. R 1 R 2 yield (%) ee (%) Me Me 35 03 Ph Me 86 42 Me Ph 73 76 Ph Ph 98 86 Stereochemical Model 6 Lewis Acid Mediated Asymmetric Nazarov Cyclizations Aggarwal and co-workers Org. Lett . 2003 , 5 , 5075

7. R equiv of Lewis Acid yield (%) ee (%) Ph 1.0 92 86 Ph 0.5 56 87 Me 1.0 72 84 Me 0.5 56 85 Stereochemical Model 7 Lewis Acid Mediated Asymmetric Nazarov Cyclizations Aggarwal and co-workers Org. Lett . 2003 , 5 , 5075

8. Entry Solvent T (°C) Yield(%) ee (%) 1 CH 2 Cl 2 rt 84 86 2 CH 2 Cl 2 40 79 85 3 Cl (CH 2 ) 2 Cl 60 91 60 4 THF rt 31 82 5 Toluene rt 44 76 6 MeCN rt - - 8 Ni(II)-Catalyzed Enantioselective Nazarov Cyclizations Togni and co-workers Chem. Commun. 2008 , 4315

9. Stereochemical Model 9 Cr(III)- Salen Catalyzed Enantioselective Nazarov Cyclizations Rawal and co-workers J. Am. Chem. Soc. 2013 , 135 , 4988

10. 10 Chiral -at-Metal Complex Catalyzed Asymmetric Nazarov Cyclizations Meggers and co-workers Adv. Synth . Catal . 2018 , 360 , 2093

11. 11 Chiral -at-Metal Complex Catalysed Asymmetric Nazarov Cyclizations

12. 12 Organocatalytic Asymmetric Nazarov Cyclizations Tius and co-workers J. Am. Chem. Soc. 2010 , 132 , 8266 Tius and co-workers Org. Lett . 2010 , 12 , 440

13. 13 Chiral Brønsted Acid Catalyzed Asymmetric Nazarov Cyclizations Tius and co-workers Angew . Chem., Int. Ed. 2014 , 53 , 6180

14. 14 https://chemistry-name-reaction.com/ To know more visit -