Intramolecular Effects of Pendant Groups

The labile aqua complex 9 (L = H2O) is a very useful precursor in this area, but it was hard to characterise fully, even with an X-ray crystal structure, because the hydrogen bonding pattern remained ambiguous out of 9a-c, the experimental data led us to prefer 9a, but only marginally. 

The DFT (B3PW91) calculations of Clot and Eisenstein predict that 9a should be preferred. Subsequent to the DFT work, cooling of 9 to — 80 °C led to 

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