Novel Isobenzofuran Generation from Silylated Lactol Leading to Desilylated or Silylated Adducts Depending on the Choice of Metal Fluorides

Abstract

A new method of isobenzofuran generation was developed by treating silylated lactol with metal fluorides. The reactions with hard early transition metal fluorides gave de-silylated dimethyl acetylenedicarboxylate (DMAD) adduct mainly. By contrast, the silyl-retained DMAD adduct, which could be used for further transformation, was also obtained depending on the choice of metal fluorides such as lanthanoides or low valent transition metal fluor­ides.

Key words

isobenzofuran - carbonyl ylides - silylated lactol - silylated isobenzofuran adducts - metal fluorides

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