Multistep reactions are often required
for the transformation of
alcohols to α-chloroacetals via the unstable intermediates aldehydes
or α-halo aldehydes. Herein, we report a simplified procedure
for practical synthesis of α-chloroacetals using 2,2,6,6-tetramethylpiperidine-1-oxyl
as a catalyst and trichloroisocyanuric acid both as an oxidant and
a chlorination reagent. The reaction is one-pot, solvent-free and
high-yielding. In addition, the α-chloroacetals have been transformed
to enol ethers through the elimination reaction in the presence of
sodium.