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DIASTEREOSELECTIVE ADDITION OF H-PHOSPHINATES TO ALKENYL KETONES UNDER PHASE-TRANSFER CONDITIONS AND SYNTHESIS OF BRIDGED BICYCLIC COMPOUNDS FOR BIOLOGICAL EVALUATION
- Date Issued:
- 2022
- Abstract/Description:
- In the present dissertation, we discuss the development of a stereoselective method for the production of phosphorus compounds that utilizes a phospha-Michael addition reaction. Separately, the design and synthesis of compounds that contain an all-carbon bridged bicyclic scaffold is reported; these compounds were used in initial SAR studies in different in vivo models. In Chapter one is presented a mechanistic framework to develop a highly diastereoselective method catalyzed by phase transfer chemistry leading to phosphinate compounds. In this method, phosphinate nucleophiles were added to various alkenyl ketones as Michael acceptors using crown ethers as phase transfer agents to obtain highly diastereoselective products with the generation of a carbon-based quaternary centers. A closed transition state mechanism is proposed to describe the diastereoselectivity observed in the reactions that is consistent with product outcome as established by X-ray crystallography. Analysis using the 31P NMR technique is also reported to ascertain the diastereomeric ratios in product formation. Using products obtained with the newly developed method, we disclose for the first time a novel phospha-heterocycle with high control of stereochemistry. Relative stereochemistry of the phosphorus containing heterocycle was reported using 2D NMR analysis. In Chapter two focus is placed on the use of acrylates as Michael acceptors in both the diastereoselective and enantioselective studies of phospha-Michael addition. In the asymmetric method development, screening of various chiral catalysts and development of HPLC method to quantify the enantiopurity of products obtained under reaction conditions are reported. The role of crown ether catalysts towards diastereoselectivity is reported.
Title: | DIASTEREOSELECTIVE ADDITION OF H-PHOSPHINATES TO ALKENYL KETONES UNDER PHASE-TRANSFER CONDITIONS AND SYNTHESIS OF BRIDGED BICYCLIC COMPOUNDS FOR BIOLOGICAL EVALUATION. |
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Name(s): |
Yadavalli, Krishna Prasad , author Lepore, Salvatore D. , Thesis advisor Florida Atlantic University, Degree grantor Department of Chemistry and Biochemistry Charles E. Schmidt College of Science |
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Type of Resource: | text | |
Genre: | Electronic Thesis Or Dissertation | |
Date Created: | 2022 | |
Date Issued: | 2022 | |
Publisher: | Florida Atlantic University | |
Place of Publication: | Boca Raton, Fla. | |
Physical Form: | application/pdf | |
Extent: | 236 p. | |
Language(s): | English | |
Abstract/Description: | In the present dissertation, we discuss the development of a stereoselective method for the production of phosphorus compounds that utilizes a phospha-Michael addition reaction. Separately, the design and synthesis of compounds that contain an all-carbon bridged bicyclic scaffold is reported; these compounds were used in initial SAR studies in different in vivo models. In Chapter one is presented a mechanistic framework to develop a highly diastereoselective method catalyzed by phase transfer chemistry leading to phosphinate compounds. In this method, phosphinate nucleophiles were added to various alkenyl ketones as Michael acceptors using crown ethers as phase transfer agents to obtain highly diastereoselective products with the generation of a carbon-based quaternary centers. A closed transition state mechanism is proposed to describe the diastereoselectivity observed in the reactions that is consistent with product outcome as established by X-ray crystallography. Analysis using the 31P NMR technique is also reported to ascertain the diastereomeric ratios in product formation. Using products obtained with the newly developed method, we disclose for the first time a novel phospha-heterocycle with high control of stereochemistry. Relative stereochemistry of the phosphorus containing heterocycle was reported using 2D NMR analysis. In Chapter two focus is placed on the use of acrylates as Michael acceptors in both the diastereoselective and enantioselective studies of phospha-Michael addition. In the asymmetric method development, screening of various chiral catalysts and development of HPLC method to quantify the enantiopurity of products obtained under reaction conditions are reported. The role of crown ether catalysts towards diastereoselectivity is reported. | |
Identifier: | FA00014015 (IID) | |
Degree granted: | Dissertation (Ph.D.)--Florida Atlantic University, 2022. | |
Collection: | FAU Electronic Theses and Dissertations Collection | |
Note(s): | Includes bibliography. | |
Subject(s): |
Bridged bicyclic compounds Chemistry, Organic Organic compounds--Synthesis |
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Persistent Link to This Record: | http://purl.flvc.org/fau/fd/FA00014015 | |
Use and Reproduction: | Copyright © is held by the author with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder. | |
Use and Reproduction: | http://rightsstatements.org/vocab/InC/1.0/ | |
Host Institution: | FAU | |
Is Part of Series: | Florida Atlantic University Digital Library Collections. |