Engineering a Dirhodium Artificial Metalloenzyme for Selective Olefin Cyclopropanation
Abstract
Artificial metalloenzymes (ArMs) formed by incorporating synthetic metal catalysts into protein scaffolds have the potential to impart to chemical reactions selectivity that would be difficult to achieve using metal catalysts alone. In this work, we covalently link an alkyne-substituted dirhodium catalyst to a prolyl oligopeptidase containing a genetically encoded L-4-azidophenylalanine residue to create an ArM that catalyses olefin cyclopropanation. Scaffold mutagenesis is then used to improve the enantioselectivity of this reaction, and cyclopropanation of a range of styrenes and donoracceptor carbene precursors were accepted. The ArM reduces the formation of byproducts, including those resulting from the reaction of dirhodiumcarbene intermediates with water. This shows that an ArM can improve the substrate specificity of a catalyst and, for the first time, the water tolerance of a metal-catalysed reaction. Given the diversity of reactions catalysed by dirhodium complexes, we anticipate that dirhodium ArMs will provide many unique opportunities for selective catalysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 24, 2015
- Accession Number
- AD1011116
Entities
People
- Hao Yang
- Jared C Lewis
- Ken Ellis-guardiola
- Poonam Srivastava
Organizations
- University of Chicago