Fürst-Plattner Rule

The Fürst-Plattner rule (also known as the trans-diaxial effect) describes the stereoselective addition of nucleophiles to cyclohexene derivatives.

[1] Cyclohexene derivatives, such as imines, epoxides, and halonium ions, react with nucleophiles in a stereoselective fashion, affording trans-diaxial addition products.

A recent example of the Fürst-Plattner rule can be seen from Chrisman et al. where limonene is epoxidized to give a 1:1 mixture of diastereomers.

The subsequent imine intermediate was treated with sodium borohydride, affording the wrong stereoisomer due to the Fürst-Plattner effect.

Unfortunately, this outcome required Woodward to perform several additional steps to complete the total synthesis of reserpine with the proper stereochemistry.