1908437-58-0Relevant academic research and scientific papers
Asymmetric Intramolecular Desymmetrization of meso-α,α′-Diazido Alcohols with Aryldiazoacetates: Assembly of Chiral C3 Fragments with Three Continuous Stereocenters
Qiao, Jin-Bao,Zhao, Yu-Ming,Gu, Peiming
, p. 1984 - 1987 (2016)
The chiral Cu-complex-catalyzed intramolecular interception of meso-α,α′-diazido alcohols with aryldiazoacetates is explored. Most of the enantioenriched α-imino esters with three continuous stereocenters are produced with good to excellent yield and enantioselectivity, and a chiral pocket model is proposed for rationalization of the asymmetric desymmetrization.
Catalytic Asymmetric Fluorination of Copper Carbene Complexes: Preparative Advances and a Mechanistic Rationale
Buchsteiner, Michael,Fürstner, Alois,Jerabek, Paul,Lehmann, Christian W.,Martinez-Rodriguez, Luis,N?thling, Nils,Patzer, Michael,Pozo, Iago
supporting information, p. 2509 - 2515 (2020/02/26)
The Cu-catalyzed reaction of substituted α-diazoesters with fluoride gives α-fluoroesters with ee values of up to 95 %, provided that chiral indane-derived bis(oxazoline) ligands are used that carry bulky benzyl substituents at the bridge and moderately bulky isopropyl groups on their core. The apparently homogeneous solution of CsF in C6F6/hexafluoroisopropanol (HFIP) is the best reaction medium, but CsF in the biphasic mixture CH2Cl2/HFIP also provides good results. DFT studies suggest that fluoride initially attacks the Cu- rather than the C-atom of the transient donor/acceptor carbene intermediate. This unusual step is followed by 1,2-fluoride shift; for this migratory insertion to occur, the carbene must rotate about the Cu?C bond to ensure orbital overlap. The directionality of this rotatory movement within the C2-symmetric binding site determines the sense of induction. This model is in excellent accord with the absolute configuration of the resulting product as determined by X-ray diffraction using single crystals of this a priori wax-like material grown by capillary crystallization.
Copper(I)-Catalyzed Enantioselective Intramolecular Aminotrifluoromethylation of O-Homoallyl Benzimidates
Mou, Xue-Qing,Rong, Feng-Ming,Zhang, Heng,Chen, Gong,He, Gang
, p. 4657 - 4661 (2019/06/17)
In the present paper, the Cu(I)-catalyzed intramolecular aminotrifluoromethylation of O-homoallyl benzimidates with Togni reagent I was reported. O-Homoallyl benzimidates equipped with terminal alkenes produced chiral 1,3-oxazines with high enantioselectivity in the presence of a chiral BOX ligand, and racemic tetrahydro-1,3-oxazepines were obtained in high yields from internal alkene derivatives with a monoprotected amino acid additive under similar conditions.
