3. |
- Malkov, Andrei V., et al.
(författare)
-
Mechanistic Dichotomy in the Asymmetric Allylation of Aldehydes with Allyltrichlorosilanes Catalyzed by Chiral Pyridine N-Oxides
- 2013
-
Ingår i: Chemistry - A European Journal. - : Wiley. - 1521-3765 .- 0947-6539. ; 19:28, s. 9167-9185
-
Tidskriftsartikel (refereegranskat)abstract
- Detailed kinetic and computational investigation of the enantio- and diastereoselective allylation of aldehydes 1 with allyltrichlorosilanes 5, employing the pyridine N-oxides METHOX (9) and QUINOX (10) as chiral organocatalysts, indicate that the reaction can proceed through a dissociative (cationic) or associative (neutral) mechanism: METHOX apparently favors a pentacoordinate cationic transition state, while the less sterically demanding QUINOX is likely to operate via a hexacoordinate neutral complex. In both pathways, only one molecule of the catalyst is involved in the rate- and selectivity-determining step, which is supported by both experimental and computational data.
|
|