title: Cu(I) catalysed cyclopropanation with enantiopure scorpionate type ligands derived from (+)-camphor or (-)-menthone.
abstract: One-pot syntheses of three new enantiopure heteroscorpionate ligands derived from (+)-camphor or (-)-menthone are described. The ligands are obtained by reacting pyrazoles derived from (+)-camphor or (-)-menthone with sodium hydride and thionyl chloride. Subsequent reactions with pyridine and various aldehydes afford the tripod ligands in multi-gram amounts. Especially the menthopyrazole based ligand 6 showed encouraging ee values up to 69% in the Cu(I) catalysed enantioselective cyclopropanation of styrene with ethyl diazoacetate.
authors.affiliation: Inorganic Chemistry, Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), University of Erlangen-Nürnberg, Egerlandstr. 1, 91058 Erlangen, Germany.
authors.forename: Tom
authors.initials: T
authors.lastname: Godau
authors.forename: Sascha M
authors.initials: SM
authors.lastname: Bleifuss
authors.forename: Astrid L
authors.initials: AL
authors.lastname: Müller
authors.forename: Thomas
authors.initials: T
authors.lastname: Roth
authors.forename: Susanne
authors.initials: S
authors.lastname: Hoffmann
authors.forename: Frank W
authors.initials: FW
authors.lastname: Heinemann
authors.forename: Nicolai
authors.initials: N
authors.lastname: Burzlaff
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D002164:Camphor / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008024:Ligands; D008610:Menthol / Q000737:chemistry*; D008968:Molecular Conformation; D011725:Pyridines / Q000737:chemistry; D017670:Sodium Compounds / Q000737:chemistry; D013237:Stereoisomerism; D013461:Sulfur Oxides / Q000737:chemistry
chemical_list: D000447:Aldehydes; D056831:Coordination Complexes; D008024:Ligands; D011725:Pyridines; D017670:Sodium Compounds; D013461:Sulfur Oxides; D008610:Menthol; C524957:sodium hydride; C023589:thionyl chloride; D002164:Camphor; D003300:Copper; C019466:menthone; C023666:pyridine