Chemistry can be defined as the study of matter and the changes it undergoes. You¡¯ll sometimes hear it called the central science because it is the connection between physics and all the other sciences, starting with biology. 4045-44-7, Name is 1,2,3,4,5-Pentamethylcyclopenta-1,3-diene, molecular formula is , belongs to catalyst-ligand compound. In a document, author is Kiran, Indukuru Naga Chaithanya, SDS of cas: 4045-44-7.
A Monocationic Zn(II) Acetate Complex of a Chiral Bisamidine Dioxolane Ligand, Naph-diPIM-dioxo-R, for the Asymmetric 1,3-Dipolar Cycloaddition of Tridentate alpha-Substituted alpha-Imino Esters and Acrylates to Multi-Substituted Prolines: Importance of an n-pi* Interaction for High Enantioselectivity
A monocationic Zn(II) acetate complex of a C-2-chiral bisamidine-type sp(2)N bidentate ligand (L-R) possessing two dioxolane oxygen n orbitals in the reaction site catalyzes, without the use of an external base, a highly efficient asymmetric 1,3-dipolar cycloaddition (1,3-DC) of tridentate alpha-substituted alpha-imino esters with acrylates, attaining up to >99:1 enantiomeric ratio with perfect regio- and diastereo-selectivities. A catalyst loading of 0.1 mol% is generally acceptable to furnish various chiral multi-substituted prolines. Both (S)-alpha-imino ester and the R enantiomer show a high level of enantioselectivity. An overall picture of the present 1,3-DC has been revealed via analyses of substrate structure/reactivity/selectivity relationships, NMR, MS, X-ray diffraction, C-12/C-13 isotope effects, rate law, and kinetics. The first success in the high performance 1,3-DC is ascribed to i) a Bronsted base/Lewis acid synergistic effect of [Zn(OAc)L-R]OTf (R cat); ii) the existence of the n orbital, which determines the position of the intermediary N,O-cis-Zn enolate (dipole) by an n-pi* non-bonding attractive interaction between the oxygen atom in L-R and the C=N moiety of the dipole; and iii) utilization of chelatable alpha-imino esters capturing Zn(II) as a tridentate ligand. A C-12/C-13 analysis has clarified that a stepwise 1,3-DC mechanism is operating.
Sometimes chemists are able to propose two or more mechanisms that are consistent with the available data. If a proposed mechanism predicts the wrong experimental rate law, however, the mechanism must be incorrect.Welcome to check out more blogs about 4045-44-7, in my other articles. SDS of cas: 4045-44-7.
Reference:
Metal catalyst and ligand design,
,Ligand Template Strategies for Catalyst Encapsulation – NCBI