Construction of Acyclic Quaternary Stereocenters via Mannich-Type Addition of α,α-Disubstituted N-tert-Butanesulfinyl Ketimines to Isatin-Derived Ketimines.
Org Lett
; 24(15): 2883-2888, 2022 04 22.
Article
in En
| MEDLINE
| ID: mdl-35420435
A Mannich reaction of deprotonated, highly enantioenriched α,α-disubstituted N-tert-butanesulfinyl ketimines with isatin-derived ketimines was developed to prepare 3-amino-3-substituted oxindoles bearing an acyclic quaternary stereogenic carbon substituted with two sterically similar groups. The excellent stereocontrol of the deprotonation enabled the formation of metalloenamine intermediates with stereodefined geometry, while the precise facial selectivity of the C-C bond formation allowed the construction of contiguous quaternary and tetrasubstituted stereocenters with excellent stereoselectivity.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Isatin
Language:
En
Journal:
Org Lett
Year:
2022
Document type:
Article