Microwave-assisted dry oxidation of 3-trialkylsilyl(germyl)prop-2-yn-1-ols to propynals and the direct conversion of acetylenic alcohols to ynimines and enynes

The efficient solvent-free microwave-assisted oxidation of 3-trialkylsilyl(germyl)prop-2-yn-1-ols with manganese dioxide or pyridinium chlorochromate to propynals and the direct conversion of acetylenic alcohols to the corresponding imines and Knövenagel adducts have been carried out.