A variety of substituted dihydroisobenzofurans can be easily synthesized in high yields by a one-pot three-component approach starting from o-bromoarylaldehydes, methanol, and terminal alkynes. The reaction occurs through an unprecedented cooperative palladium/base promoted coupling/addition/cyclization sequence. (C) 2010 Elsevier Ltd. All rights reserved.
Selective Base-Promoted Synthesis of Dihydroisobenzofurans by Domino Addition/Annulation Reactions of ortho-Alkynylbenzaldehydes
nucleophilic addition/annulation reaction of ortho-alkynylbenzaldehydes in the presence of methanol. The reactions of aryl-, trimethylsilyl- and diethoxymethyl-substituted alkynylbenzaldehydes occurred with complete regioselectivity in good to excellent yields undermicrowaveirradiation. The reactions of alkyl-substituted alkynylbenzaldehydes took place with good yields and high regioselectivity only when