103790-08-5Relevant articles and documents
Diastereoselective Desymmetrization of p-Quinamines through Regioselective Ring Opening of Epoxides and Aziridines
Jadhav, Sandip B.,Chegondi, Rambabu
, p. 10115 - 10119 (2019)
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.
(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)
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.
Lewis Base Promoted, Direct 1,4-Conjugate Addition to Quinone Imine Ketals: Efficient Access to Unsymmetrical Diaryl Sulfones
Liu, Teng,Liu, Jianjun,Shen, Xianfu,Xu, Jianbin,Nian, Beifang,He, Ni,Zeng, Shunqun,Cheng, Feixiang
, p. 1365 - 1376 (2019)
An alternative approach with eco-friendliness and high efficiency for the preparation of unsymmetrical diaryl sulfones has been developed. The strategy takes advantage of the reaction of sulfonyl hydrazides with quinone imine ketals catalyzed by DABCO (triethylenediamine) in ethanol. This transformation proceeds via a Lewis base promoted, direct 1,4-conjugate addition/sulfonylation/alcohol elimination reaction sequence. The protocol provides an efficient approach to access an array of diverse unsymmetrical diaryl and heterodiaryl sulfones, aryl alkyl sulfones and aryl vinyl sulfones in good to excellent yields.
Accessing bridged bicyclic compounds or meta carbon-functionalized anilines from the dearomatization of anilines
Wang, Linfei,Wang, Shuo-En,Wang, Weibin,Fan, Renhua
, p. 5775 - 5778 (2013)
The oxidative dearomatization of anilines was combined with a domino Michael addition, providing a series of nitrogen-containing bridged bicyclic compounds in moderate to excellent yields. The bridged bicyclic compound could be converted into the correspo
Enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinone monoimines
Liu, Hui,Yan, Yingkun,Zhang, Jiayan,Liu, Min,Cheng, Shaobing,Wang, Zhouyu,Zhang, Xiaomei
supporting information, p. 13591 - 13594 (2020/11/17)
The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinone monoimines was realized using a chiral phosphoric acid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations of two products were assigned by X-ray crystal structural analyses and a plausible reaction mechanism was proposed. This journal is
