1449770-03-9Relevant articles and documents
Enantioselective Desymmetrization of para-Quinamines through an Aminocatalyzed Aza-Michael/Cyclization Cascade Reaction
Pantaine, Lo?c,Coeffard, Vincent,Moreau, Xavier,Greck, Christine
, p. 3674 - 3677 (2015)
An unprecedented organocatalytic asymmetric desymmetrization of para-quinamines leading to functionalized hydroindoles, a common motif in many alkaloids, has been reported. The ability of diarylprolinol silyl ethers to promote iminium and enamine activation of α,β-unsaturated aldehydes in one catalytic cycle is the centerpiece of the strategy involving a challenging aza-Michael/intramolecular cyclization cascade reaction. A range of prochiral para-quinamines and α,β-unsaturated aldehydes were investigated to afford 16 examples of hydroindoles possessing four contiguous stereocenters including one quaternary carbon. The hydroindole structures include multiple orthogonal functionalities, which underwent various transformations.
[3 + 2]-Annulation of Prop-2-ynylsulfonium Salts: Access to Hydroindol-5-ones Containing a Methylthio Group
Jia, Penghao,Zhang, Qinglong,Jin, Hongxing,Huang, You
, p. 412 - 415 (2017)
An unprecedented [3 + 2]-annulation of prop-2-ynylsulfonium salts and p-quinamines was developed, affording a series of hydroindol-5-ones with a methylthio group in moderate to good yields under mild conditions. In this reaction, the prop-2-ynylsulfonium
Diastereoselective Desymmetrization of p-Quinamines through Regioselective Ring Opening of Epoxides and Aziridines
Jadhav, Sandip B.,Chegondi, Rambabu
, p. 10115 - 10119 (2019/12/24)
A highly diastereoselective desymmetrization of p-quinamines via regioselective ring opening of epoxides and aziridines under mild conditions has been developed. A chairlike six-membered transition state with minimized 1,3-diaxial interactions explains the relative stereoselectivity of the cyclization reaction. This transition-metal free [3 + 3] annulation reaction provides rapid access to fused bicyclic morpholines and piperazines with a tetrasubstituted carbon center in high yields. In addition, it also allows the synthesis of enantioenriched products by using easily accessible chiral nonracemic epoxides and aziridines.
Nitrogen-Bridged, Natural Product Like Octahydrobenzofurans and Octahydroindoles: Scope and Mechanism of Bridge-Forming Reductive Amination via Caged Heteroadamantanes
Wales, Steven. M.,Adcock, Holly V.,Lewis, William,Hamza, Daniel,Moody, Christopher J.
supporting information, p. 4696 - 4704 (2018/09/14)
The biological significance of sp3-rich synthetic scaffolds with natural product like features yet distinct global frameworks is being increasingly recognized in medicinal chemistry and biochemistry. Taking inspiration from the vast array of bi
Phosphine-catalyzed intramolecular Rauhut-Currier reaction: Enantioselective synthesis of hydro-2: H -indole derivatives
Jin, Hongxing,Zhang, Qinglong,Li, Erqing,Jia, Penghao,Li, Ning,Huang, You
supporting information, p. 7097 - 7101 (2017/09/07)
A highly enantioselective intramolecular Rauhut-Currier reaction catalyzed by a multifunctional chiral aminophosphine catalyst was reported. A series of hydro-2H-indole derivatives that bear an all-carbon quaternary center were obtained in high yields (up to 94%), and excellent diastereo- and enantioselectivities (up to >20:1 dr and >99% ee). And this reaction could be performed on a gram scale using 2 mol% catalyst loading.
(3 + 2)-Annulation of p-Quinamine and Aryne: A Strategy to Construct the Multisubstituted Hydrocarbazoles
Xu, Dengyu,Zhao, Yulong,Song, Dengpeng,Zhong, Zhuliang,Feng, Shangbiao,Xie, Xingang,Wang, Xiaolei,She, Xuegong
, p. 3600 - 3603 (2017/07/15)
A strategy for the synthesis of multisubstituted hydrocarbazoles has been developed through (3 + 2)-annulation of p-quinamines and arynes. In this way, new analogs of hydrocarbazoles with quaternary carbon center can be synthesized in satisfactory yield under mild conditions. Furthermore, this (3 + 2)-annulation can be easily scaled-up, and the products can be modified through simple transformation.
Ligand and substrate effects during Pd-catalyzed cyclizations of alkyne-tethered cyclohexadienones
Tello-Aburto, Rodolfo,Kalstabakken, Kyle A.,Harned, Andrew M.
supporting information, p. 5596 - 5604 (2013/09/12)
The effects of ligand and substrate choice on the Pd-catalyzed cyclization of alkyne-tethered cyclohexadienones were examined. In the presence of a chiral ligand, the enantioselectivity of the desymmetrization is remarkably sensitive to structural changes in both the ligand and the substrate. Additionally, the regioselectivity of the reaction (5- vs. 6-membered ring formation) is dependent on the proximity of heteroatoms to the alkyne.
