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.
Chiral phosphoric acid catalyzed enantioselective addition of thiols to in situ generated ketimines: Synthesis of N , S -ketals
作者:Rajshekhar A. Unhale、Nagaraju Molleti、Nirmal K. Rana、Sivasankaran Dhanasekaran、Subhrajyoti Bhandary、Vinod K. Singh
DOI:10.1016/j.tetlet.2016.11.114
日期:2017.1
The chiral Brønsted acid catalyzed enantioselective 1,2-addition of thiols to in situgenerated ketimines, derived from 3-hydroxyisoindolinones, has been studied. The protocol provides a variety of isoindolinone-derived N,S-ketals in up to 98% yield and up to 99% enantioselectivity. The products have been converted to a known non-nucleoside HIV-1 reverse transcriptase inhibitor and a 1,3-thiazine derivative
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