A Single-Step Synthesis of Symmetrical 1,3-Diarylisobenzofurans

A convenient single-step synthesis of various symmetrically substituted 1,3-diarylisobenzofiirans from readily available 3-methoxy-3H-isobenzofuran-l-one (la) and two equivalents of aryl Grignard reagents is described. The title compounds are obtained in medium to high isolated yields. Crude isobenzofuran has also been trapped by maleimide, furnishing pure Diels-Alder adduct almost quantitatively.