Formula: C18H13BCl3F4N3O. The protonation of heteroatoms in aromatic heterocycles can be divided into two categories: lone pairs of electrons are in the aromatic ring conjugated system; and lone pairs of electrons do not participate. Compound: (5aS,10bR)-2-(2,4,6-Trichlorophenyl)-4,5a,6,10b-tetrahydro-2H-indeno[2,1-b][1,2,4]triazolo[4,3-d][1,4]oxazin-11-ium tetrafluoroborate, is researched, Molecular C18H13BCl3F4N3O, CAS is 1214711-48-4, about Kinetic resolution of β-ketoesters with quaternary stereocenters via a carbene-catalyzed benzoin reaction. Author is Zehra, Syeda Tazeen; Zhang, Guoxiang; Yang, Shuang; Fang, Xinqiang.
Chiral β-ketoesters (S)-2-H(O)CC6H4CH2C(R2)(C(O)R1)C(O)OR3 [R1 = Ph, thiophen-2-yl, cyclopropyl, etc.; R2 = allyl, benzyl, (4-methylphenyl)methyl, etc.; R3 = Et, Bn] and Et (R)-2-benzoyl-2-(3-oxopropyl)pent-4-enoate bearing fully substituted carbon centers are important building blocks in organic synthesis. Mono-substituted ketoesters rac-2-H(O)CC6H4CH2C(R2)(C(O)R1)C(O)OR3 and Et 2-benzoyl-2-(3-oxopropyl)pent-4-enoate have been widely used to synthesize the above compounds through asym. additions or substitutions. The limitations of these protocols mainly exist in the substrate scopes, and α-Me or α-fluoro-substituted β-ketoesters or acetyl acetates are frequently used owing to their relatively higher reactivity. To break through this limitation, N-heterocyclic carbene e.g., I catalyzed kinetic resolution to achieve the access to enantioenriched β-ketoesters with quaternary stereocenters was employed. Sterically more bulky groups such as benzyl, allyl, Ph and cyclopropyl groups are all tolerated using this method.
Compounds in my other articles are similar to this one((5aS,10bR)-2-(2,4,6-Trichlorophenyl)-4,5a,6,10b-tetrahydro-2H-indeno[2,1-b][1,2,4]triazolo[4,3-d][1,4]oxazin-11-ium tetrafluoroborate)Formula: C18H13BCl3F4N3O, you can compare them to see their pros and cons in some ways,such as convenient, effective and so on.
Reference:
Quinuclidine – Wikipedia,
Quinuclidine | C7H13N | ChemSpider