130638-48-1Relevant academic research and scientific papers
Nucleophilic Additions to the Chiral Rhenium Alkene Complexes 5-C5H5)(NO)(PPh3)(H2C=CHR)>BF4 (R = H, Me, CH2CH2Me, Ph or CH2Ph): Regio-, Diastereo- and Enantio-selectivities
Peng, Tang-Sheng,Arif, Atta M.,Gladysz, J. A.
, p. 1857 - 1866 (2007/10/02)
Reactions of alkene complexes 5-C5H5)(NO)(PPh3)(H2C=CHR)>BF4 1 (R = H a, Me b, CH2CH2Me c, Ph d or CH2Ph e) and LiCuMe2 in tetrahydrofuran (thf) at -80 deg C gave the primary, β-branched alkyl complexes 5-C5H5)(NO)(PPh3)(CH2CHMeR)> 2 (79-99percent).No secondary alkyl complexes derived from additions to the unsubstituted =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 5-C5H5)(NO)(PPh3)> and a crystal structure determination show that attack occurs on the C=C face anti to the rhenium.Reactions of 1a or 1b (in thf) with NaOMe-MeOH gave predominantly the 2-methoxyalkyl complexes 5-C5H5)(NO)(PPh3)> (R = H 4a or Me 4b) (92-97percent).Analogous reactions of 1c or 1d gave 81-77:19-23 mixtures of 4c or 4d and the alkenyl complexes (E)-5-C5H5)(NO)(PPh3)(CH=CHR)> (85-71percent).A similar reaction of 1e gave mainly the allyl complex 5-C5H5)(NO)(PPh3)(CH2CH=CHPh)>.
