title: An effective use of benzoic anhydride and its derivatives for the synthesis of carboxylic esters and lactones: a powerful and convenient mixed anhydride method promoted by basic catalysts.
abstract: Various carboxylic esters are obtained at room temperature in excellent yields with high chemoselectivities from nearly equimolar amounts of carboxylic acids and alcohols using 2-methyl-6-nitrobenzoic anhydride with triethylamine by the promotion of a basic catalyst such as 4-(dimethylamino)pyridine. A variety of lactones are also prepared in high yields at room temperature from the corresponding omega-hydroxycarboxylic acids with use of 2-methyl-6-nitrobenzoic anhydride in the presence of 4-(dimethylamino)pyridine. A similar reaction occurs with triethylamine when using a catalytic amount of 4-(dimethylamino)pyridine 1-oxide as an effective promoter for the intramolecular condensation reaction. These methods are successfully applied to the synthesis of erythro-aleuritic acid lactone and an eight-membered-ring lactone moiety of octalactins A and B. The efficiency of the cyclizations is compared to those of other reported lactonizations.
authors.affiliation: Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan. shiina@ch.kagu.sut.ac.jp
authors.forename: Isamu
authors.initials: I
authors.lastname: Shiina
authors.forename: Mari
authors.initials: M
authors.lastname: Kubota
authors.forename: Hiromi
authors.initials: H
authors.lastname: Oshiumi
authors.forename: Minako
authors.initials: M
authors.lastname: Hashizume
mesh_terms: D000812:Anhydrides / Q000737:chemistry*; D001565:Benzoates / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D004952:Esters / Q000138:chemical synthesis*; D005021:Ethylamines / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis*; D015394:Molecular Structure; D010169:Palmitic Acids / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C417980:4-(dimethylamine)pyridine; D000812:Anhydrides; D001565:Benzoates; D002264:Carboxylic Acids; D004952:Esters; D005021:Ethylamines; D007783:Lactones; D010169:Palmitic Acids; D011725:Pyridines; C059860:aleuritolic acid; C102988:benzoic anhydride; C016162:triethylamine