Asymmetric Synthesis of 2‐Thiocyanato‐2‐(1‐aminoalkyl)‐substituted 1‐Tetralones and 1‐Indanones with Tetrasubstituted Carbon Stereogenic Centers via Cooperative Cation‐Binding Catalysis

In this study, the concept of cooperative cation‐binding catalysis was applied for direct generation of two contiguous trisubstituted and tetrasubstituted stereogenic centers. Using the readily accessible chiral oligoethylene glycol (oligoEG) as a cation‐binding catalyst, asymmetric Mannich reaction...

Full description

Saved in:
Bibliographic Details
Published in:Advanced synthesis & catalysis 2017-06, Vol.359 (11), p.1879-1891
Main Authors: Yu, Lei, Wu, Xiaoyan, Kim, Mun Jong, Vaithiyanathan, Venkataramasubramanian, Liu, Yidong, Tan, Yu, Qin, WenLing, Song, Choong Eui, Yan, Hailong
Format: Article
Language:English
Subjects:
2-(1-Boc- amino)benzyl-1-oxo-2-thiocyanato-1,2,3,4-tetrahydronaphthalenes
Accessibility
Asymmetry
Binding
Catalysis
Catalysts
cation-binding catalysis
Cations
chiral oligoethylene glycol
Imines
Ketones
Mannich reaction
Potassium
Potassium fluoride
Stereoselectivity
tetrasubstituted carbon stereogenic centers
β-amino-α-thiocyanates
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this study, the concept of cooperative cation‐binding catalysis was applied for direct generation of two contiguous trisubstituted and tetrasubstituted stereogenic centers. Using the readily accessible chiral oligoethylene glycol (oligoEG) as a cation‐binding catalyst, asymmetric Mannich reactions of α‐thiocyanato cyclic ketones as Mannich donors were performed with α‐amidosulfones as the bench‐stable imine precursors in the presence of potassium fluoride as the base, affording 2‐thiocyanato‐2‐(1‐aminoalkyl)‐substituted 1‐tetralones and 1‐indanones possessing fully substituted C–SCN centers. The salient features of this process include (i) a transition metal‐free and operationally simple procedure, (ii) direct use of α‐amidosulfones as bench‐stable precursors of sensitive imines, (iii) direct enolization of racemic cyclic α‐thiocyanato ketones and (iv) excellent stereoselectivity with up to 99% ee and >20:1 diastereoselectivity (anti:syn). This protocol is easily scalable and provides a new approach for the syntheses of some biologically relevant products possessing fully substituted C–SCN centers.
ISSN:1615-4150
1615-4169
DOI:10.1002/adsc.201700015