The mechanism of the garryfoline–cuauchichicine rearrangement has been investigated using the epimeric (–)-kaur-16-en-15-ols as models. The 15β-ol is shown to rearrange rapidly in mineral acid at room temperature to 16R-(–)-kaur-15-one by a 15, 16-hydride shift. The 16α-ol, like veatchine, is stable under these conditions. The contrast in the ability of these epimeric alcohols to undergo 15, 16-hydride shifts is discussed. Under the same ...
