Cyclobutadiene. 3. Photolysis of Matrix-isolated 13 C-Labeled Bicyclopyranones, Journal of the American Chemical Society, 99, 4153 (1977).

Professor Krantz studied the stereochemistry of electrocyclic reactions, but his forte was photochemical generation of highly reactive species in inert gas metrices. His trophies included the elusive cyclobutadiene and thiirene, characterized by analysis of vibrational spectra of isotopically labeled specimens.