title: Brucine diol-copper-catalyzed asymmetric synthesis of endo-pyrrolidines: the mechanistic dichotomy of imino esters.
abstract: Enantio- and diastereodivergent approaches to pyrrolidines are described by using catalyst- and substrate-controlled reaction pathways. A concerted endo-selective [3 + 2]-cycloaddition pathway is developed for the reaction of methyl imino ester, whereas endo-pyrrolidines with an opposite absolute stereochemical outcome are prepared by using the stepwise reaction pathway of tert-butyl imino ester. The development of catalyst- and substrate-controlled stereodivergent approaches highlights the inherent substrate-catalyst interactions in the [3 + 2]-cycloaddition reactions of metalated azomethine ylides.
authors.affiliation: Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis , Indianapolis, Indiana 46037, United States.
authors.forename: Jian-Yuan
authors.initials: JY
authors.lastname: Li
authors.forename: Hun Young
authors.initials: HY
authors.lastname: Kim
authors.forename: Kyungsoo
authors.initials: K
authors.lastname: Oh
mesh_terms: D001391:Azo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D015394:Molecular Structure; D011759:Pyrrolidines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013331:Strychnine / Q000031:analogs & derivatives* / Q000737:chemistry; D013882:Thiosemicarbazones / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D001391:Azo Compounds; D011759:Pyrrolidines; D013882:Thiosemicarbazones; C512188:azomethine; C083806:brucine; D003300:Copper; D013331:Strychnine