Iridium-catalyzed asymmetric [3+2] annulation of aromatic ketimines with alkynes via C–H activation: unexpected inversion of the enantioselectivity induced by protic acids
A cationic iridium/binap catalyst enabled the asymmetric [3 + 2] annulation of cyclic N-acyl ketimines with internal alkynes via C-Hactivation to give spiroaminoindene derivatives with high enantioselectivity. The stereochemical...
Enantioselective [3 + 2] annulation between 1,3-dienes and N-acyl ketimines in situ generated from 3-aryl-3-hydroxyisoindolin-1-ones proceeded via CâH activation to give spiroaminoindane derivatives in high yields with high regio- and enantioselectivity, which is realized by use of an Ir/chiral diene catalyst.
Synthesis of Functionalized Isoindolinones via Calcium Catalyzed Generation and Trapping of <i>N</i>-Acyliminium Ions
作者:Ashley J. Basson、Mark G. McLaughlin
DOI:10.1021/acs.joc.0c00482
日期:2020.4.17
Herein we report our full investigation into the calcium catalyzed generation and trapping of N-acyliminium ions from readily available 3-hydroxyisoindolinones. We have successfully employed a range of traditional nucleophiles including carbon, nitrogen, and sulfur containing reactive partners. The reaction is tolerant to a wide range of functionalities and provides high value scaffolds in good to
A chiral Brønsted acid-catalyzed highly enantioselective Mannich-type reaction of α-diazo esters with <i>in situ</i> generated <i>N</i>-acyl ketimines
作者:Rajshekhar A. Unhale、Milon M. Sadhu、Sumit K. Ray、Rayhan G. Biswas、Vinod K. Singh
DOI:10.1039/c8cc01436a
日期:——
A chiral phosphoric acid-catalyzed asymmetricMannich-typereaction of α-diazo esters with in situ generated N-acyl ketimines, derived from 3-hydroxyisoindolinones has been demonstrated in this communication. A variety of isoindolinone-based α-amino diazo esters bearing a quaternary stereogenic center were afforded in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). Furthermore
Rh(III)-Catalyzed Diastereodivergent Spiroannulation of Cyclic Imines with Activated Alkenes
作者:Bingxian Liu、Panjie Hu、Ying Zhang、Yunyun Li、Dachang Bai、Xingwei Li
DOI:10.1021/acs.orglett.7b02678
日期:2017.10.6
Rh(III)-catalyzed [3 + 2] annulation of cyclic N-sulfonyl or N-acyl ketimines with activated alkenes has been realized, leading to the synthesis of spirocycles with three continuous stereogenic centers. This atom-economic reaction proceeded efficiently under mild and redox-neutral conditions via a C–H activation pathway, and the coupling is diastereodivergent, with the diastereoselectivity being controlled