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Parella R, Jakkampudi S, Bora P, Sakkani N, Zhao JCG. Domino Michael/Michael reaction catalyzed by switchable modularly designed organocatalysts. Org Biomol Chem 2021; 20:163-172. [PMID: 34877959 DOI: 10.1039/d1ob01991k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The domino Michael/Michael reaction between (E)-7-aryl-7-oxohept-5-enals and trans-cinnamaldehydes was investigated by using modularly designed organocatalysts (MDOs). It was found that both the enamine and iminium catalytic modes of the MDOs are switchable and can be individually switched on and off by using appropriate combinations of the precatalyst modules and the reaction conditions. When both the enamine and iminium catalysis modes of the MDOs are switched on, the desired domino reaction products can be obtained in good yields and stereoselectivities under optimized conditions.
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Affiliation(s)
- Ramarao Parella
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-069, USA.
| | - Satish Jakkampudi
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-069, USA.
| | - Pranjal Bora
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-069, USA.
| | - Nagaraju Sakkani
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-069, USA.
| | - John C-G Zhao
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-069, USA.
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Bora P, Jakkampudi S, Parella R, Sakkani N, Dai Q, Bihani M, Arman HD, Zhao JCG. Diastereodivergent synthesis of 4-oxocyclohexanecarbaldehydes by using the modularly designed organocatalysts upon switching on their iminium catalysis. Chem Commun (Camb) 2021; 57:5334-5337. [PMID: 33928958 DOI: 10.1039/d1cc01020d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cinchona thiourea moiety in the self-assembled modularly designed organocatalysts (MDOs) switches off the iminium catalysis of these catalysts. In this study, it was found that the inhibited iminium catalysis could be switched on by using an appropriate weak acid and that, once the iminium catalysis was switched on, these catalysts could be applied for the highly stereoselective and diastereodivergent synthesis of 4-oxocyclohexanecarbaldehydes via a domino reaction between ketones and α,β-unsaturated aldehydes.
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Affiliation(s)
- Pranjal Bora
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Satish Jakkampudi
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Ramarao Parella
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Nagaraju Sakkani
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Qipu Dai
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Manisha Bihani
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - Hadi D Arman
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
| | - John C-G Zhao
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
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Direct Catalytic Asymmetric Synthesis of Disubstituted 4-Oxocyclohexanecarbaldehydes from Acetone and Cinnamaldehyde Derivatives. Org Lett 2021; 23:1566-1571. [DOI: 10.1021/acs.orglett.0c04277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Hu YJ, Wang XB, Li SY, Xie SS, Wang KD, Kong LY. Facile synthesis of spiro chromanone-tetrahydrothiophenes with three contiguous stereocenters via sulfa-Michael/aldol cascade reactions. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2014.11.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Sengoden M, Vijay M, Balakumar E, Punniyamurthy T. Efficient pyrrolidine catalyzed cycloaddition of aziridines with isothiocyanates, isoselenocyanates and carbon disulfide “on water”. RSC Adv 2014. [DOI: 10.1039/c4ra08902b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The cycloaddition of aziridines with isothiocyanates, isoselenocyanates and carbon disulfide is described using pyrrolidine on water. This protocol affords a potential route for the construction of the five membered heterocycles with high yields.
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Affiliation(s)
- Mani Sengoden
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039, India
| | - Murugan Vijay
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039, India
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