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Chapter 1: Part A: A Unique Approach Of Preparing 3,3-Disubstituted Oxindoles From Acyclic Tetrasubstituted Aldehydes: Total Synthesis Of (-)-Coerulescine And (-)-Coixspirolactam A, Chapter 1: Part B: Synthetic Scope Of Brønsted Acid Catalyzed Reactions Of Carbonyl Compounds And Ethyl Diazoacetate,, Md Shahnawaz Ali

Theses and Dissertations

CHAPTER 1: PART A: A UNIQUE APPROACH OF PREPARING 3,3-DISUBSTITUTED OXINDOLES FROM ACYCLIC TETRASUBSTITUTED ALDEHYDES: TOTAL SYNTHESIS OF (-)-COERULESCINE AND (-)-COIXSPIROLACTAM A(-)-Coerulescine and (-)-coixspirolactam A, two naturally occurring compounds characterized with an all-carbon quaternary center containing a spirooxindole, have been synthesized asymmetrically. The key feature of their total synthesis involves a novel rational construction of the chiral 3,3-disubstituted oxindole core from the acyclic chiral tetrasubstituted aldehyde. The later scaffold was prepared in high enantioselectivity (up to 86%) from the ethyl 3-hydroxy-2-(2-nitrophenyl)acrylate 1 by exploring both intermolecular and intramolecular Pd-mediated asymmetric allylic allylations (Pd-AAA). A through optimization of these approaches is …