Asymmetric Induction via the Structural Indenyl Effect

Autor: Robert W. Baker
Rok vydání: 2018
Předmět:
Zdroj: Organometallics. 37:433-440
ISSN: 1520-6041
0276-7333
DOI: 10.1021/acs.organomet.7b00841
Popis: Constrained geometry, planar chiral, dichloro[η5:κS-indenyl-sulfanyl]rhodium complex (pS)-1 reacts with (E)-2-pentene in the presence of silver hexafluoroantimonate to afford syn,syn-1,3-dimethyl-π-allyl complex (pS)-2 in 88% yield. Reaction of (pS)-2 with the sodium or tetrabutylammonium salts of dimethyl malonate anion provided dimethyl 2-[(1R,2E)-1-methyl-2-buten-1-yl]-1,3-propanedioate ((R)-3) in 68–70% yield and 66–68% enantiomeric excess. NMR analysis and density functional theory calculations establish that asymmetric induction is substantially determined by the electronic asymmetry of the indenyl ligand polarizing the preferred site of nucleophilic attack on the π-allyl ligand toward the terminal carbon that is syn to the indenyl benzo-ring.
Databáze: OpenAIRE