Frontispiece: Large Isotope Effects in Organometallic Chemistry

Hydrogen atoms sometimes react far faster than deuterium atoms. Reactions can proceed over 100 times faster with hydrogen, or the deuterium reaction may not be observed at all. Examples of large kinetic isotope effects throughout organotransition metal chemistry are reviewed. Possible causes for these observed effects are discussed, including vibrational differences, multistep reactions, and proton tunneling. Artwork depicting a hydrogen cheetah and a deuterium sloth by Caitlyn Y. Tong. Read more in the Minireview by M. A. Bowring et al. on page 14800 ff.