title: Palladium(II)-catalyzed intramolecular 1,4-oxyacyloxylation of conjugated dienes. A stereocontrolled route to fused six-membered lactones and pyrans.
abstract: Stereocontrolled palladium(II)-catalyzed intramolecular 1,4-oxidations of dienyl acids and alcohols proceed under mild conditions to give fused delta-lactones and pyrans, respectively, in good yields. The stereo- and regioselectivity was affected by the presence of LiCl and solvent composition (HOAc/acetone). The products obtained were used for further functionalizations using copper(I)-mediated reactions. Stoichiometric reactions of preformed dibutylcyanocuprates with pyrans containing an allylic acetate gave cis- and trans-fused ring systems with high gamma-selectivity and in high yields.
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Renzo C
authors.initials: RC
authors.lastname: Verboom
authors.forename: B Anders
authors.initials: BA
authors.lastname: Persson
authors.forename: Jan-E
authors.initials: JE
authors.lastname: Bäckvall
mesh_terms: D000215:Acylation; D000466:Alkadienes / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry; D002384:Catalysis; D003300:Copper / Q000737:chemistry; D003500:Cyclization; D007783:Lactones / Q000138:chemical synthesis*; D018021:Lithium Chloride / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D011714:Pyrans / Q000138:chemical synthesis*; D012997:Solvents / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000466:Alkadienes; D002264:Carboxylic Acids; D007783:Lactones; D009942:Organometallic Compounds; D011714:Pyrans; D012997:Solvents; D010165:Palladium; D003300:Copper; D018021:Lithium Chloride