85926-79-0Relevant academic research and scientific papers
Reactions of Diazo Compounds and Chiral Rhenium Alkylidene Complexes of the Formula 5-C5H5)Re(NO)(PPh3)(=CHR)+PF6-; A Versatile and Highly Stereoselective Route to Alkene Complexes
Wang, Yan,Gladysz, John A.
, p. 213 - 220 (2007/10/02)
The methylidene complex 5-C5H5)Re(NO)(PPh3)(=CH2)>+ PF6- or the Re=CD2 analog react with diazo compounds N2CHR in CH2Cl2 at -80 deg C to give alkene complexes 5-C5H5)Re(NO)(PPh3)(η2-H2C=CHR)>+ PF6- or D2C=HR analogs.The Re=C geometric isomers of benzylidene complex 5-C5H5)Re(NO)(PPh3)(=CHPh)>+ PF6- and CH2N2 react to give opposite configurational diastereomers of styrene complex 5-C5H5)Re(NO)(PPh3)(η2-H2C=CHPh)>+ PF6-.Stereochemical features of these reactions are analyzed in detail, and are interpreted in terms of models involving (a) attack of the diazo compound upon the Re=C face opposite to the bulky PPh3 ligand, (b) an antiperiplanar disposition of the Re=C and C-N2 bonds in the transition state, utilizing the diazo carbon face that minimizes interactions of the substituent (R) and cyclopentadienyl ligand, and (c) N2 loss from the resulting intermediate 5-C5H5)Re(NO)(PPh3)(CHR'CHRN2)>+ PF6- via a conformer with antiperiplanar P-Re-CHR'-C and Re-CHR'-CHR-N linkages, with anchimeric assistance of the rhenium fragment d orbital HOMO from the backside. - Key Words: Rhenium complexes / Alkylidene complexes / Diazo compounds / Alkene complexes
REGIOSPECIFIC AND STEREOSPECIFIC REACTIONS OF Ph3C + PF6 - WITH RHENIUM ALKYLS ( eta -C5H5)Re(NO)(PPh3)(R). alpha -vs. beta -HYDRIDE ABSTRACTION.
Kiel,Lin,Bodner,Gladysz
, p. 4958 - 4972 (2007/10/02)
This study mapped the structural features which control the regiochemistry of hydride abstraction by Ph//3C** plus PF//6** minus from alkyls eta -C//5H//5)Re(NO)(PPh//3)(R). Accurate predictions can now be made regarding the reactivity of yet unsynthesize
