title: Highly stereoselective chemoenzymatic synthesis of the 3H-isobenzofuran skeleton. Access to enantiopure 3-methylphthalides.
abstract: A straightforward synthesis of (S)-3-methylphthalides has been developed, with the key asymmetric step being the bioreduction of 2-acetylbenzonitriles. Enzymatic processes have been found to be highly dependent on the pH value, with acidic conditions being required to avoid undesired side reactions. Baker's yeast was found to be the best biocatalyst acting in a highly stereoselective fashion. The simple treatment of the reaction crudes with aqueous HCl has provided access to enantiopure (S)-3-methylphthalides in moderate to excellent yields.
authors.affiliation: Organic and Inorganic Department, Instituto Universitario de Biotecnología de Asturias, Universidad de Oviedo Calle Julián Clavería s/n, Oviedo 33006, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Mangas-Sánchez
authors.forename: Eduardo
authors.initials: E
authors.lastname: Busto
authors.forename: Vicente
authors.initials: V
authors.lastname: Gotor-Fernández
authors.forename: Vicente
authors.initials: V
authors.lastname: Gotor
mesh_terms: D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D001572:Benzofurans; C082022:phthalide