Mg-promoted carbon-acylation of aromatic aldehydes and ketones

Reductive cross-coupling of aromatic aldehydes and ketones with aliphatic acid chlorides promoted by Mg turnings in DMF at room temperature brought about efficient C-acylation to afford the corresponding α-acyloxy-α-aryl ketones in good yields. Treatment of α-methoxy or α-acetoxyacetophenones under similar conditions gave the corresponding α-acyloxystyrenes exclusively. The reaction may be initiated by electron transfer from Mg to the carbonyl groups of the substrates.