Work

Enzyme-Controlled Nitrogen-Atom Transfer Enables Regiodivergent C–H Amination

Year: 2014

Type: article

Abstract: We recently demonstrated that variants of cytochrome P450BM3 (CYP102A1) catalyze the insertion of nitrogen species into benzylic C-H bonds to form new C-N bonds. An outstanding challenge in the field of C-H amination is catalyst-controlled regioselectivity. Here, we report two engineered variants of P450BM3 that provide divergent regioselectivity for C-H amination-one favoring amination of benzylic C-H bonds and the other favoring homo-benzylic C-H bonds. The two variants provide nearly identical kinetic isotope effect values (2.8-3.0), suggesting that C-H abstraction is rate-limiting. The 2.66-Å crystal structure of the most active enzyme suggests that the engineered active site can preorganize the substrate for reactivity. We hypothesize that the enzyme controls regioselectivity through localization of a single C-H bond close to the iron nitrenoid.

Source: Journal of the American Chemical Society

DOI: 10.1021/ja509308v

Authors: Todd K. Hyster, Christopher C. Farwell, Andrew R. Buller, John A. McIntosh, Frances H. Arnold

Institution: California Institute of Technology

Language: English

Topic: Metal-Catalyzed Oxygenation Mechanisms

Subfield: Inorganic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500