enantioselectivity การใช้

• Often, high chemo-and enantioselectivity can be achieved.
• This reaction occurs with high enantioselectivity, but low activity.
• However, the enantioselectivity of asymmetric cyclopropanations may depend profoundly on the solvent.
• Aryl, heteroaryl, and alkenyl imines were all suitable for good yield and enantioselectivity.
• The diastereoselectivity and the enantioselectivity could be achieved at the same time using chiral BINAP ligand.
• However the C 2  symmetry of the ligand is also important in controlling this enantioselectivity.
• Similarly, a chiral amino alcohol allows for extremely high enantioselectivity in the allylation of ketones.
• The enantioselectivity is further controlled by hydrogen bonding between the proline carboxylic acid group and the imine.
• Other members are C2 symmetry which limits the number of possible reaction pathways and thereby increasing enantioselectivity.
• This was predicted and then confirmed to increase the enantioselectivity and activity of metal complexes of SEGPHOS.
• Selectivity in terms of regioselectivity, diastereoselectivity and enantioselectivity is therefore an important criterion for many organic reactions.
• Significantly, the reaction can be run on a 5 mmol scale without loss of yield or enantioselectivity.
• If the amine is chiral, then the dihydroxylation can proceed with enantioselectivity ( see Sharpless asymmetric dihydroxylation ).
• Enantioselectivity issues associated with the use of BH 3 as the reducing agent for the CBS reduction have been reported.
• The inherent difficulties of controlling enantioselectivity in intermolecular reactions made the development of an intermolecular asymmetric Stetter reaction a challenge.
• In the realm of asymmetric methods, both the Sharpless epoxidation and Jacobsen epoxidation surpass asymmetric dioxirane oxidations in enantioselectivity.
• Many studies have shown that in zinc addition reactions, the enantioselectivity is not linearly correlated with catalyst enantiomeric purity.
• It was proposed that the fluorinated backbone helps to lock the conformation of the catalyst in a way the increases enantioselectivity.
• The addition of a phosphinoyl group to the nitrogen of the ketimine allowed for high enantioselectivity up to 98 % ee.
• In another example, a symmetrical cyclic imide is subjected to asymmetric deprotonation resulting in a chiral product with high enantioselectivity.