Solvent‐Mediated C3/C7 Regioselective Switch in Chiral Phosphoric Acid‐Catalyzed Enantioselective Friedel‐Crafts Alkylation of Indoles with α‐Ketiminoesters
作者:Yunlong Zhao、Lu Cai、Tongkun Huang、Shanshui Meng、Albert S. C. Chan、Junling Zhao
DOI:10.1002/adsc.201901380
日期:2020.3.17
The first solvent‐mediated tunable C3/C7 regio‐ and enantioselective Friedel‐Crafts alkylation of 4‐aminoindoles with α‐ketimino esters has been developed. This catalysis allows the highly regioselective formation of indole C3 and C7 alkylation products, both in high yields (up to 96%) and excellent enantioselectivities (up to 99% ee). Mechanism study revealed that the hydrogen‐bonding interactions
Synthesis of Multisubstituted 1,4-Dihydrobenzoxazin-2-ones through a One-Pot Nucleophilic N-Alkylation/C-Alkylation of Cyclic α-Imino Esters
作者:Lode De Munck、Carlos Vila、Carolina Pons、José Pedro
DOI:10.1055/s-0036-1588742
日期:2017.6
via a one-pot N-alkylation/C-alkylation reactions is reported. A nucleophilic N-alkylation of 2-oxobenzoxazine-2-carboxylates with organozinc reagents with good selectivities and in moderate to good yields is described. Moreover, the synthesis of multisubstituted 1,4-dihydrobenzoxazine-2-ones bearing a tetrasubstituted carbon atom via a one-pot N-alkylation/C-alkylation reactions is reported.
Reactive Ketimino Radical Acceptors: Intermolecular Alkyl Radical Addition to Imines with a Phenolic Hydroxyl Group
作者:Hideto Miyabe、Yousuke Yamaoka、Yoshiji Takemoto
DOI:10.1021/jo052518x
日期:2006.3.1
Intermolecular carbon radical addition to the carbon−nitrogen double bond of ketimines was studied. In the study on the reactivity of various aldimines, we found that the aldimine 7 having a phenolic hydroxyl group shows an excellent reactivity toward nucleophilic carbon radicals. A remarkable effect of phenolic hydroxyl group is assumed to be the stabilization of intermediate aminyl radical provided by a
A highly efficient Mukaiyama–Mannich reaction of N-Boc isatin ketimines and other active cyclic ketimines using difluoroenol silyl ethers catalyzed by Ph<sub>3</sub>PAuOTf
作者:Jin-Sheng Yu、Jian Zhou
DOI:10.1039/c5ob01895a
日期:——
catalyst for the addition of difluoroenol silylethers to N-Boc isatin ketimines and other two kinds of active cyclic ketimines. This represents the first Au(I)-catalyzed Mukaiyama–Mannich reaction, and the corresponding non-fluorinated enolsilylether proves to be even much more reactive under the same conditions. This method paves the way to the total synthesis of difluoromethylated analogues of AG-041R
Synthesis of Multi-Substituted 1,4-Benzoxazine Using an Umpolung Reaction with 2-Oxo-1,4-benzoxazine-3-carboxylates
作者:Makoto Shimizu、Takanori Tanaka、Isao Mizota、Kazuto Umezu、Akinori Ito
DOI:10.3987/com-16-s(s)52
日期:——
This report describes a one-pot synthesis of multi-substituted 1,4-benzoxazine derivatives by atom economical N,C-dialkylation reaction of 1,4-benzoxazine derivatives with various organozinc reagents and ketene silyl acetals (KSA).