Hydrosilylation of cinchonidine and 9-O-TMS-cinchonidine with triethoxysilane: application of 11-(triethoxysilyl)-10,11-dihydrocinchonidine as a chiral modifier in the enantioselective hydrogenation of 1-phenylpropane-1,2-dione

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: Lindholm A, Maki-Arvela P, Toukoniitty E, Pakkanen TA, Hirvi JT, Salmi T, Murzin DY, Sjoholm R, Leino R
Förläggare: ROYAL SOC CHEMISTRY
Publiceringsår: 2002
Tidskrift: Journal of the Chemical Society, Perkin Transactions 1
Tidskriftsakronym: J CHEM SOC PERK T 1
Nummer: 23
Artikelns första sida, sidnummer: 2605
Artikelns sista sida, sidnummer: 2612
Antal sidor: 8
ISSN: 1472-7781


Abstrakt

The detailed synthesis and characterization of (-)-11-(triethoxysilyl)-10,11-dihydrocinchonidine (4), a starting material for the immobilization of (-)- cinchonidine on silica based supports, is described. Compound 4 together with its precursors 9-O-(trimethylsilyl)cinchonidine (2) and 9-O-(trimethylsilyl)-11-(triethoxysilyl)-10,11-dihydrocinchonidine (3) were employed as chiral modifiers in the hydrogenation of a prochiral diketone, 1-phenylpropane-1,2-dione, over a heterogeneous Pt/Al2O3 catalyst using cinchonidine (1) as a reference modifier. The unexpected enhancement of ee induced by 4, demonstrating the positive effect of distal modifier substitution, is discussed in the light of molecular modeling and NMR studies.

Senast uppdaterad 2019-10-12 vid 03:01