Design, synthesis, and evaluation of chiral thiophosphorus acids as organocatalysts
Karen R Winters1, Jean-Luc Montchamp1
1Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, United States.
Abstract:
A series of P-stereogenic chiral phosphorus acids (CPAs) were synthesized to determine the requirements for efficient asymmetric organocatalysis. In order to eliminate the need for C 2-symmetry in common CPAs, various scaffolds containing C 1-symmetrical thiophosphorus acids were chosen. These new compounds were synthesized and evaluated in the asymmetric transfer hydrogenation of 2-phenylquinoline. Although the efficacy of the thiophosphorus acids was disappointing for this reaction, the work should be useful for developing structural design elements.
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