Zhou, You-Yun published the artcileSide-Arm-Promoted Highly Enantioselective Ring-Opening Reactions and Kinetic Resolution of Donor-Acceptor Cyclopropanes with Amines, Category: benzoxazole, the publication is Journal of the American Chemical Society (2012), 134(22), 9066-9069, database is CAplus and MEDLINE.
In the presence of a nonracemic tridentate trisoxazoline ligand I and nickel(II) perchlorate, bis(neopentyl) cyclopropanedicarboxylates II [R = Me3CCH2; R1 = Ph, 4-ClC6H4, 4-BrC6H4, 3,4-Cl2C6H3, 4-O2NC6H4, 4-MeC6H4, 3-MeC6H4, 4-MeOC6H4, 2-MeOC6H4, 3,4-(MeO)2C6H3, 2-thienyl, (E)-PhCH:CH, H2C:CH, 2-furyl] underwent enantioselective ring-opening reactions with amines R2R3NH [R2 = (E)-Me3CO2CCH:CHCH2, PhCH2, TBDMSOCH2CH2, EtO2CCH2, H2C:CHCH2, (MeO)2CHCH2; R3 = PhCH2, 4-MeOC6H4CH2, Ph; TBDMS = tert-butyldimethylsilyl] to give nonracemic γ-aminodiesters (R)-R1CH(NR2R3)CH2CH(CO2R)2 [R = Me3CCH2; R1 = Ph, 4-ClC6H4, 4-BrC6H4, 3,4-Cl2C6H3, 4-O2NC6H4, 4-MeC6H4, 3-MeC6H4, 4-MeOC6H4, 2-MeOC6H4, 3,4-(MeO)2C6H3, 2-thienyl, (E)-PhCH:CH, H2C:CH, 2-furyl; R2 = (E)-Me3CO2CCH:CHCH2, PhCH2, TBDMSOCH2CH2, EtO2CCH2, H2C:CHCH2, (MeO)2CHCH2; R3 = PhCH2, 4-MeOC6H4CH2, Ph] in 59-99% yields and in 80-98% ee. In the presence of I and nickel(II) perchlorate, reaction of II (R = Me3CCH2; R1 = Ph, 4-ClC6H4, 4-BrC6H4, 4-MeC6H4, 3-MeC6H4) underwent kinetic resolution with BnNHR2 [R2 = (E)-Me3CO2CCH:CHCH2, PhCH2, (MeO)2CHCH2] to give nonracemic II in 39-46% yields and in 90-97% ee. The structure of the nickel(II) perchlorate complex with an unsym. analog of I was determined by X-ray crystallog.
Journal of the American Chemical Society published new progress about 1239015-11-2. 1239015-11-2 belongs to benzoxazole, auxiliary class TOX Ligands, name is (3aS,3a’S,3a”S,8aR,8a’R,8a”R)-2,2′,2″-(Propane-1,2,2-triyl)tris(8,8a-dihydro-3aH-indeno[1,2-d]oxazole), and the molecular formula is C17H19N3O7S, Category: benzoxazole.
Referemce:
https://en.wikipedia.org/wiki/Benzoxazole,
Benzoxazole | C7H5NO – PubChem