New palladium-catalysed access to 3-(1′-indanylidene) phthalide, precursor of the core of fredericamycin A
An efficient synthesis of 3-(1′-indanilydene) phthalide is described via a palladium-catalysed biscyclisation step.
Bouyssi,Balme
p. 1191 - 1193
(2007/10/03)
SYNTHESIS OF 3-(1'-INDANYLIDENE)PHTHALIDES VIA WITTIG-HORNER REACTION OF DIMETHYL PHTHALIDE-3-PHOSPHONATES AND THEIR CONVERSION TO THE BCDE RING PART OF FREDERICAMYCIN A
Wittig-Horner reaction of dimethyl phthalide-3-phosphonates with 1-indanones in the presence of bases was investigated.The 3-(1'-indanylidene)phthalides obtained above were transformed into dibenzeno-1,4-diketospirononanes, the BCDE ring system of fredericamycin A, by consecutive treatments with diisobutylaluminum hydride and pyridinium dichromate.