Dr. Anuvab Das

Anuvab Das
Department of Chemistry
California Institute of Technology
Abstract

Transient C–H Amination Intermediates: From Structural Characterization to Application in Biocatalysis

Defects Metal–ligand (M–L) multiply bonded complexes hold a central place in inorganic chemistry and catalysis. These species have played a critical role in the articulation of important bonding principles, and are critical intermediates in a variety of challenging chemical transformations. The reactivity of these species simultaneously renders them attractive intermediates for catalysis but challenging synthetic targets to observe and characterize. The first part of this talk will introduce novel photochemical strategies for generating reactive M–L fragments under conditions suitable for time-resolved or cryogenic steady-state characterization. This photochemistry facilitates the use of in situ crystallography to characterize transient intermediates via single-crystal-to-single-crystal transformation. These experiments represent a new paradigm in the characterization of reactive intermediates in catalysis. 

In the second part, we will explore how the principles of protein evolution can be leveraged to harness these transient intermediates for catalytic processes not naturally occurring. The engineering of heme proteins allows for the selective functionalization of inert C–H bonds, generating nitrogen-containing molecules from basic feedstock chemicals. This highlights the significant role of biocatalysis and protein engineering in contemporary synthesis.

Anuvab Das

Born and raised in India, Anuvab completed his B.Sc. and M.Sc. in Chemistry from Presidency College (Kolkata) and IIT Kharagpur, respectively. He then moved to the US to pursue his doctoral studies with Prof. David C. Powers at Texas A&M University. His graduate work focused on the characterization of reactive intermediates involved during nitrene transfer reactions, using in situ crystallography. At present, he is a postdoctoral scholar with Prof. Frances H. Arnold at Caltech, where he is working on the development and characterization of new-to-nature amination reactions with heme proteins.

Hosted by Professor Ian Tonks