New research progress on 13676-54-5 in 2021. Chemo-enzymatic cascade processes are invaluable due to their ability to rapidly construct high-value products from available feedstock chemicals in a one-pot relay manner. 13676-54-5, Name is Bismaleimide, molecular formula is C21H14N2O4, belongs to pyrrolines compound, is a common compound. In a patnet, author is Feiken, N, once mentioned the new application about 13676-54-5, Quality Control of Bismaleimide.
1,3-dipolar cycloaddition to the Fe-N=C fragment .17. Diastereoselectivity with C-2- and non-C-2-symmetric chirally N-substituted alpha-diimine ligands, R*-N=C(H)-C(R’)=N-R* and C5H4N-2-C(R’)=N-R*, with dimethyl acetylenedicarboxylate (DMAD) and methyl propiolate (MP). Decomplexation of the pyrrolinone ligand of Fe(CO)(3)(pyrrolinone) complexes
The 1,3-dipolar cycloaddition reaction of Fe[R*-DAB(H;H)](CO)(3) (6k; R*-DAB(H;H)=R*-N=C(H)-C(H)=N-R*) with dimethyl acetylenedicarboxylate (DMAD), in which the R*-DAB(H;H) ligand is C-2-symmetric and is chirally N-substituted, gives the two expected diastereomers with low diastereoselectivity, due to a small difference in the rate constants of the two reactive C=N groups in 6k exposing their re and si faces, respectively. The 1,3-dipolar cycloaddition reaction of Fe(alpha-diimine)(CO)(3) (1, 6m) with DMAD and methyl propiolate (MP), in which a non-C-2-symmetric alpha-diimine ligand (R*-DAB(H;Me) and Py-2-C(R’)=N-R* (R*,R’-PyCa) is chirally N-substituted, gives the two expected diastereomers with medium to high diastereoselectivity. The diastereoselectivity with the non-C-2-symmetric alpha-diimine ligands, which have only one reactive imino group, depends on the size of the chiral group R*, the distance of the chiral group to the reacting centers, and the type of dipolarophile. The two starting complexes (1 and 6m) exist in solution in the form of two rapidly interconverting diastereomeric conformers I and II. In contrast to the C-2-symmetric case, the free energies of activation for the two different conformers and their respective concentrations may be quite different here. The diastereoselectivities could not be influenced by variation of temperature, solvent, or the additional ligand. Kinetic resolution by a cycloreversion reaction could be excluded by the use of a chiral additional ligand and an achiral alpha-diimine ligand (i-Pr, H-PyCa, or i-Pr-DAB(H; H)). X-ray crystal structures have been determined from the respective diastereomeric mixtures of the pyrrolinone complex 5cks and the [2.2.2] bicyclic product 7aks. The structures of the [2.2.2] bicyclic product 4aks and of the free pyrrolinone ligand 8als have been determined using diastereomerically pure products. The 5-(2-pyridyl)pyrrolin-2-one ligands 8 are decomplexed from their precursors 5 by Me(3)NO, air oxidation, exchange by CO, and oxidative reactions with dihalogens or H2O2.
The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 13676-54-5 is helpful to your research. Quality Control of Bismaleimide.
Reference:
Pyrroline – Wikipedia,
,1-Pyrroline | C4H7N – PubChem