STUDIES CONCERNING NUCLEOPHILIC PHOSPHINE CATALYSIS AND DESIGNS OF NEW CHIRAL AMINOPHOSPHINES TOWARD ASYMMETRIC PHOSPHINE-CATALYZED REACTIONS
- Author(s): Khong, San Ngoc
- Advisor(s): Kwon, Ohyun
- et al.
Phosphinocatalysis has been used among us as a short term for nucleophilic phosphine catalysis. The information in chapter 1 will focus on how phosphinocatalysis was discovered, who contributed to the early-day developments of this field, and what have been achieved in the field. Chapter 2 will cover phosphine-allene chemistry in which the equillibrium between phosphonium dienolate and vinylogous ylide was reaffirmed. Two new phosphine-mediated transformations were discovered in this chemistry: vinylogous aldol/P-to-C aryl migration by reaction of phosphonium dienolate with an aromatic aldehyde and vinylogous Wittig olefination by reaction of vinylogous ylide with an aromatic aldehyde. Chapter 3 will discuss the development of a one-pot procedure for phosphine-initiated general base-catalyzed quinoline synthesis and of its variation to quinolone synthesis. A number of 3-substituted and 3,4-disubstituted quinolines, as well as 3-substituted 4-quinolones have been generated from this methodology. Chapter 4 involves the designs of new chiral aminophosphines toward the asymmetric version of phosphine-catalyzed double Michael reaction. The aminophosphines were particularly designed based on the presumption that the anchimeric assistance of the amino group onto the phosphonium phosphorous was essentially significant to the reaction's success. The chiral element was designed to be on the amino group, which would endow the asymmetric environment to the reactive center via anchimeric assistance during the reaction. A small collection of chiral aminophosphines were eventually prepared based on this design. Chapter 5 was an extension on the design of chiral aminophosphines. However, the new design of chiral aminophosphines was not based on any specific asymmetric chemical transformations. This design was centered on the steric-directing mode of asymmetric induction and then would be tested toward various phosphinocatalysis reactions.