Single and Stepwise Double Hydrogen Transfer in H-bonds of Medium Strength

4 Intramolecular Single and Stepwise Double Hydrogen Transfer in H-bonds of Medium Strength 

When the hydrogen bonds become stronger the hydrogen transfer rates increase as the barriers are lowered. This is the case in a series of compounds discussed in this section. 

4 but are not further discussed as kinetic isotope effects were not obtained. 

The reaction rates are similar in the polycrystalline porphyrin analog dimethyl- 

In polycrystalline tetramethyldibenzotetraaza[14]annulene (TTAA, Fig. 6.30) a related tautomerism was observed [49]. By a combination of solid state and 

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