The reactions of (ary1oxy) magnesium bromides with a-branched aliphatic aldehydes in apolar solvents have been investigated in order to obtain information on the role of 0- quinone methide intermediates 8 or 9 in controlling the selectivity of the reactions of phenolic substrates and carbonyl compounds, which usually give a complex mixture of products. These reactions are characterized by high ortho regioselectivity, giving 2, 2'- ...
