Jump to main content
Jump to site search

Issue 11, 1995
Previous Article Next Article

Nucleophilic additions to the chiral rhenium alkene complexes [Re(η5-C5H5)(NO)(PPh3)(H2C[double bond, length half m-dash]CHR)]BF4(R = H, Me, CH2CH2Me, Ph or CH2Ph): regio-, diastereo- and enantio-selectivities

Abstract

Reactions of alkene complexes [Re(η5-C5H5)(NO)(PPh3)(H2C[double bond, length half m-dash]CHR)]BF41(R = H a, Me b, CH2CH2Me c, Ph d or CH2Ph e) and LiCuMe2 in tetrahydrofuran (thf) at –80 °C gave the primary, β-branched alkyl complexes [Re(η5-C5H5)(NO)(PPh3)(CH2CHMeR)]2(79–99%). No secondary alkyl complexes derived from additions to the unsubstituted [double bond, length half m-dash]CH2 termini were detected. Product diastereomer and enantiomer ratios matched those of the reactants. Thus, the additions are regiospecific, diastereospecific and enantiospecific. A chemical correlation involving [Re(η5-C5H5)(NO)(PPh3){CH2CH(CD3)Me}] and a crystal structure determination [(SR,RS)-2e·0.5C6H14] show that attack occurs on the C[double bond, length half m-dash]C face anti to the rhenium. Reactions of 1a or 1b(in thf) with NaOMe–MeOH gave predominantly the 2-methoxyalkyl complexes [Re(η5-C5H5)(NO)(PPh3){CH2CH(OMe)R}](R = H 4a or Me 4b)(92–97%). Analogous reactions of 1c or 1d gave 81–77:19–23 mixtures of 4c or 4d and the alkenyl complexes (E)-[Re(η5-C5H5)(NO)(PPh3)(CH[double bond, length half m-dash]CHR)](85–71%). A similar reaction of 1e gave mainly the allyl complex [Re(η5-C5H5)(NO)(PPh3)(CH2CH[double bond, length half m-dash]CHPh)].

Back to tab navigation

Article type: Paper
DOI: 10.1039/DT9950001857
J. Chem. Soc., Dalton Trans., 1995, 1857-1865

  •   Request permissions

    Nucleophilic additions to the chiral rhenium alkene complexes [Re(η5-C5H5)(NO)(PPh3)(H2C[double bond, length half m-dash]CHR)]BF4(R = H, Me, CH2CH2Me, Ph or CH2Ph): regio-, diastereo- and enantio-selectivities

    T. Peng, A. M. Arif and J. A. Gladysz, J. Chem. Soc., Dalton Trans., 1995, 1857
    DOI: 10.1039/DT9950001857

Search articles by author

Spotlight

Advertisements