Simple One-Pot Conversion of Aldehydes and Ketones into Enals

Significance

The hydroboration of ethoxyacetylene with borane-dimethyl sulfide complex and subsequent transmetalation with diethylzinc provides after reaction with aldehydes or ketones and acidic workup the corresponding C₂-homologated α,β-unsaturated aldehydes in high yields. Alternatively, the one-pot workup using either anilinium hydrochloride, ethane-1,2-dithiol or acetic anhydride gives the unsaturated imine, dithiolane or gem-diacetate, respectively.