A facile access to masked isobenzofurans ; High exo-stereoselectivity in the Diels-Alder reactions of 4,7-dihydro-4,7-ethanoisobenzofuran.
作者:Dominique Stephan、Alain Gorgues、André Le Coq
DOI:10.1016/s0040-4039(00)94257-6
日期:——
The isobenzofuran derivatives precursors a-c are readily prepared from ; their Diels-Alder adducts with cis-dienophiles present a stereochemistry endoexo from b,c and, interestingly, only exo (towards the furan moiety) from a.
Cis-ethylenic analogues 1 and ortho-benzenic analogues 2 of TTF undergo a rapid acid mediated intramolecular cyclization into the corresponding cycloisomers 1' and 2' whose structures are confirmed by X-ray diffraction; as shown by cyclic voltammetry, compounds 1 may act as convenient precursors of organic metals.
GORGUES A.; COQ A., TETRAHEDRON LETT., 1979, NO 50, 4829-4832