Fred McLafferty: Pioneer of Mass Spectrometry and the McLafferty Rearrangement

Major contributions

McLafferty is best known for the rearrangement reaction that bears his name. The McLafferty rearrangement describes a characteristic cleavage and hydrogen transfer seen in the mass spectra of certain carbonyl compounds; recognizing this pattern helps analysts deduce molecular structure from fragmented ions McLafferty rearrangement. He also played a leading role in bringing together gas chromatography and mass spectrometry, working with Roland Gohlke to develop practical GC–MS techniques that allowed complex mixtures to be separated and identified routinely GC–MS development.

Beyond pattern recognition and chromatography coupling, McLafferty contributed to methods for fragmenting gas-phase ions, including work connected to electron-based dissociation approaches. These fragmentation strategies expanded the toolkit for sequencing and structural analysis of organic molecules and peptides electron capture and fragmentation.

How his work is used

• Interpretation rules such as the McLafferty rearrangement remain part of training for analysts and forensic scientists.
• GC–MS, developed in part through his efforts, is now a routine method in environmental monitoring, drug testing, food safety, and petrochemical analysis.
• Advances in ion fragmentation techniques underlie modern proteomics and structural mass spectrometry.

McLafferty's achievements were recognized by his election to the U.S. National Academy of Sciences in 1982, an honor reflecting his influence on chemical analysis and instrumentation NAS membership. His long academic career included mentoring younger scientists and contributing to textbooks and reviews that codified practical interpretation strategies for mass spectra.

He died in Ithaca, New York, on December 26, 2021, at age 98. Contemporary accounts and remembrances emphasize both the technical depth of his work and its lasting practical impact on analytical chemistry and related applied fields obituary and remembrances.