Convenient Synthesis of Building-Blocks for Pyridine/Piperidine-Decorated Crown Ethers

A convenient way to 1-(pyridin-2-yl)ethan-1,2-diol, 2-(oxiran-2-yl)pyridine and two diastereomeric forms of 1-(piperidin-2-yl)ethan-1,2-diol, valuable building-blocks for the synthesis of functionalized crown ethers, has been developed. It is based on the Wagner oxidation or NBS-mediated epoxydation of 2-vinylpyridine, and the Schwenk-Papa reduction of 1-(pyridin-2-yl)ethan-1,2-diol, accompanied by fractional crystallization of a diastereo-meric mixture of the target product.