Heteroatom directed aromatic lithiation reactions for the synthesis of condensed heterocyclic compounds

Electron-Transfer-Induced Reductive Cleavage of Phthalans: Reactivity and Synthetic Applications

“…Synthesis of Isochroman-3-ones. As an application of the reductive electrophilic substitution of phthalans, we have investigated their ring expansion to substituted 1,4-dihydro-3 H -2-benzopyran-3-ones (substituted isochroman-3-ones), which are useful intermediates in the synthesis of biologically active heterocyclic compounds. , …”

“…Synthesis of Dihydroisocoumarins. As a further application, we have developed a simple procedure allowing the transformation of the diols obtained by the reductive electrophilic substitution of 1a with aldehydes into 3-substituted 3,4-dihydro-1 H -2-benzopyran-1-ones (dihydroisocoumarins), a class of compounds which can be found in several plants and, due to their potential biological activity, are the subject of continuous synthetic efforts. , …”

“…Taking into account the relative amount of recovered diols, compounds 9a and 9b were obtained in 56% and 71% isolated yields, respectively. The dihydroisocoumarin 9b is the methyl ether of the aglycon of (±)-dihydrohomalicine, a naturally occurring glycoside …”