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Updated: Jun 19, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Computational study of the lipase-mediated desymmetrisation of 2-substituted-propane-1,3-diamines
Eduardo García-Urdiales1, Eduardo Busto, Nicolás Ríos-Lombardía
1Departmento de Química Orgánica e Inorgánica, Instituto Universitario de Biotecnología de Asturias, Universidad de Oviedo, Spain.
Abstract:
The enantioselectivity displayed by the lipase from Pseudomonas cepacia towards a wide range of prochiral 2-substituted-propane-1,3-diamines was studied by means of molecular dynamics simulations (MDS). In all cases the enzyme allows the recovery of the corresponding amino carbamates of R configuration. However, the enantioselectivity is only synthetically useful if no ortho substituent is present and the aromatic ring is directly bonded to the 2-carbon of the 1,3-diamine core. Analysis of the MDS trajectories revealed that the homologation of 2-aryl substituents by means of a methylene group lowers enantioselectivity by alleviating the conformational tension of the slow-reacting orientations due to unfavourable intramolecular contacts between the ortho carbons of the aryl group and the nucleophilic nitrogen, as well as between the chiral carbon and the oxyanion. Additionally, the relative solvent accessible surfaces of the atoms of the aryl ring nicely correlate with the effect of the location of the substituent on enantioselectivity.
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