title: Enantioenrichment of a tungsten dearomatization agent utilizing chiral acids.
abstract: A method is described for the resolution of the versatile dearomatization reagent TpW(NO)(PMe3)(η(2)-benzene), in which the 1,3-dimethoxybenzene (DMB) analogue of this complex is synthesized. In turn, the coordinated arene of TpW(NO)(PMe3)(DMB) is protonated with either D or L dibenzoyl tartaric acid (DBTH2) in a butanone/water or 2-pentanone/water solution. Sustained stirring of this mixture results in the selective precipitation of a single form of the diastereomeric salt [TpW(NO)(PMe3)(DMBH)](DBTH). After isolation, the salt can be redissolved, and the DMB ligand can be deprotonated and exchanged for benzene to produce the desired product TpW(NO)(PMe3)(η(2)-benzene) in either its R or S form. The absolute configuration of the tungsten stereocenter in TpW(NO)(PMe3)(η(2)-benzene) can be determined in either case by substituting the naturally occurring terpene (S)-β-pinene for benzene and evaluating the 2D NMR spectrum of the corresponding β-pinene complex.
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Lankenau
authors.affiliation: ‡Department of Chemistry, University of Richmond, Richmond, Virginia 23173, United States.
authors.forename: Diana A
authors.initials: DA
authors.lastname: Iovan
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: Jared A
authors.initials: JA
authors.lastname: Pienkos
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Salomon
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: Sisi
authors.initials: S
authors.lastname: Wang
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Harrison
authors.affiliation: ‡Department of Chemistry, University of Richmond, Richmond, Virginia 23173, United States.
authors.forename: William H
authors.initials: WH
authors.lastname: Myers
authors.affiliation: †Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
authors.forename: W Dean
authors.initials: WD
authors.lastname: Harman