Diastereoselective C-alkylation of aldimines, derived from chiral α-carbon heteroatom-substituted aldehydes, with triethylborane. Application to the synthesis of benzylisoquinolines

The one-pot reaction of a chiral aldehyde, p -methoxyaniline or p -fluoroaniline, and triethylborane produces the corresponding alkylated chiral amine with high yields and diastereoisomeric ratios. Stereocontrol is induced by the presence of a heteroatom in the α-position to the aldehyde. In the cas...

Full description

Saved in:
Bibliographic Details
Published in:RSC advances 2023-03, Vol.13 (13), p.8976-8984
Main Authors: Fuentes-Ríos, David, Muñoz, Carmen, Díaz, Amelia, Sarabia, Francisco, López-Romero, J. Manuel
Format: Article
Language:English
Subjects:
Aldehydes
Aliphatic amines
Alkylation
Chemistry
Imines
Stereoselectivity
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The one-pot reaction of a chiral aldehyde, p -methoxyaniline or p -fluoroaniline, and triethylborane produces the corresponding alkylated chiral amine with high yields and diastereoisomeric ratios. Stereocontrol is induced by the presence of a heteroatom in the α-position to the aldehyde. In the case of alkylation of imines derived from chiral aliphatic amines, good yields and moderate to high diastereoselectivity are obtained: yields are significantly better when the preformed imine is used in the reaction with triethyl borane, and diastereoselectivity of the reactions largely depends on the structure of the chiral aliphatic amine. The methodology is successfully applied to the synthesis of romneine, a natural benzylisoquinoline. The one-pot alkylation of aldimines produces alkylated chiral amines with high yields and diastereoisomeric ratios. Stereocontrol is induced by the presence of a heteroatom (X) in the α-position to the starting aldehyde.
ISSN:2046-2069
2046-2069
DOI:10.1039/d3ra01397a