Green Chemistry for Catalytic Carbonyl Propargylation

University Of Texas At Austin, Austin TX

Investigators

Abstract

This project focuses on the development of metal-catalysts that promote direct byproduct-free C-C coupling of alcohols and pi-unsaturated compounds. In the proposed funding period, this novel pattern of reactivity will be applied to enyne-mediated propargylation of carbonyl compounds from the alcohol oxidation level. A feature of these transformations is the ability to achieve carbonyl addition directly from the alcohol oxidation state by exploiting alcohols and conjugated enynes as redox-pairs. Here, alcohol dehydrogenation drives reductive generation of allenylmetal species and aldehyde electrophiles, which combine to furnish homo-propargyl alcohols. Unlike classical approaches to carbonyl propargylation, which require carbonyl electrophiles in combination with pre-metallated nucleophiles (e.g. organo-tin or organo-magnesium reagents), the C-C coupling processes employ pi-unsaturated compounds as surrogates to pre-metallated nucleophiles, thus avoiding generation of stoichiometric metallic waste. Further, through the direct C-C coupling of alcohols, one circumvents discrete redox manipulations otherwise required for pre-generation of aldehyde electrophiles. With this award, the Chemical Synthesis Program is supporting the research of Professor Michael J. Krische of the Department of Chemistry and Biochemistry at the University of Texas at Austin. Professor Krische, who leads the Center for Green Chemistry and Catalysis, is engaged in the development of catalytic C-C bond forming processes that enable sustainable, byproduct-free manufacture of chemical products from abundant, renewable resources. Successful development of the methodology will have an impact on any area of activity in which the synthesis of organic molecules is needed, such as the pharmaceutical, chemical, agricultural industry, and the biological and chemical research activities. In addition, this project will provide excellent training of students, from pre-undergraduate to post-doctoral, including those from groups historically underrepresented in the sciences.