NIH shift

https://doi.org/10.1351/goldbook.N04142
The @I03130@ hydrogen @M03920@ which can be observed in enzymatic and chemical hydroxylations of aromatic rings. It is evidenced by appropriate @D01648@ @L03425@, i.e.
N04142.png
In enzymatic reactions the NIH shift is generally thought to derive from the @R05194@ of arene oxide intermediates, but other pathways have been suggested. (NIH stands for U.S. National Institutes of Health where the shift was discovered.)
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1145 [Terms] [Paper]