Du, Yao published the artcileAsymmetric reductive Mannich reaction to ketimines catalyzed by a Cu(I) complex, Computed Properties of 503538-69-0, the publication is Journal of the American Chemical Society (2008), 130(48), 16146-16147, database is CAplus and MEDLINE.
A highly diastereoselective reductive Mannich coupling of ketimines and α,β-unsaturated esters was developed using CuOAc-PPh3 or CuOAc-MePPh2 complex as a catalyst (5 mol %) and pinacolborane as a reducing reagent. The reaction was easily conducted at room temperature, and the substrate generality was broad. This platform methodol. was extended to the first catalytic asym. reductive Mannich reaction of ketimines using CuOAc-DIFLUORPHOS as the catalyst (10 mol %). Switching the reducing reagent from pinacolborane to (EtO)3SiH was key to inducing the high enantioselectivity (82-93% ee). High diastereoselectivity was also maintained (3:1∼30:1). Thus, products containing contiguous tetra- and trisubstituted carbons were catalytically synthesized with high stereoselectivities. Products were converted to α,β,β-trisubstituted (β2,3,3) amino acid derivatives without any racemization and epimerization through simple treatment under acidic conditions. This method is the first entry of the catalytic asym. synthesis of β2,3,3-amino acid derivatives, which constitute important chiral building blocks of biol. significant mols.
Journal of the American Chemical Society published new progress about 503538-69-0. 503538-69-0 belongs to dioxole, auxiliary class (Atropisomeric Bisphosphine Ligands, name is (R)-5,5′-Bis(diphenylphosphino)-2,2,2′,2′-tetrafluoro-4,4′-bi-1,3-benzodioxole, and the molecular formula is C38H24F4O4P2, Computed Properties of 503538-69-0.
Referemce:
https://en.wikipedia.org/wiki/1,3-Benzodioxole,
Dioxole | C3H4O2 – PubChem