Directionality of Proton Transfer in Solutions. Three Systems of Known Angularity

Article abstract of DOI:10.1021/ja00353a024

Three compounds were synthesized each possessing rigid carbon frameworks that hold an oxygen base near a mobile C-H proton in well-defined angular and distance relationships: 2-iodo-4-hydroxyindan, endo-5-hydroxybicyclo<2.2.1>heptan-2-one, and endo-2-hydroxy-exo-6-bromomethyl<2.2.1>heptane.Effective proton transfer was detected with the second and third compounds but not the first.The data suggest that C-to-O proton transfer with severely bent O/H/C angles (106 deg) is permissible if the O-H distance is less than the sum of the van der Waals radii. "Long distance" catalysis at active sites of enzymes appears unlikely.