fulltext.study @t Gmail

New heterogeneous catalysts for the synthesis of chiral amino acids: Functionalization of organic resins with chiral salen complexes

Paper ID Volume ID Publish Year Pages File Format Full-Text
54751 47025 2013 5 PDF Available
Title
New heterogeneous catalysts for the synthesis of chiral amino acids: Functionalization of organic resins with chiral salen complexes
Abstract

•First study with heterogeneous salen catalysts to obtain asymmetric amino acids.•4 new heterogeneous catalysts with V and Al salen complexes on polystyrene resins.•V catalysts more efficient than the Al heterogeneous catalysts.•V heterogeneous catalyst can be used in 3 runs without loss of conversion and ee.

Four new heterogeneous catalysts were synthesized by covalent attachment of vanadium(V) and aluminum(III) salen complexes to polystyrene polymers, namely, Merrifield and JandaJel resins. The solid catalysts were characterized by analytical and spectroscopic techniques and tested in the asymmetric addition of hydrogen cyanide (generated in situ from TMSCN) to N-benzyl benzylimine (Strecker type reaction). Heterogeneous vanadium(V) catalysts are more efficient than the Al(III) catalysts, as expected from comparison with the corresponding homogeneous systems. The activity of the vanadium(V) heterogeneous catalysts is similar to the homogenous counterpart (after 4 h of reaction at −40 °C using 10 mol% of catalysts), while the enantiomeric excess was slightly inferior to the one obtained with the corresponding homogeneous catalysts. The Janda-V(V) heterogeneous catalyst can be reused by simple filtration up to three times without significative loss of conversion and enantioselectivity. This is the first study dedicated to the synthesis of asymmetric amino acids through the Strecker reaction using heterogeneous salen catalysts.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (106 K)Download as PowerPoint slide

Keywords
Strecker reaction; Heterogeneous enantioselective catalysis; Vanadium(V) salen complex; Aluminum(III) salen complex; Polystyrene resins
First Page Preview
New heterogeneous catalysts for the synthesis of chiral amino acids: Functionalization of organic resins with chiral salen complexes
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Catalysis Today - Volumes 218–219, December 2013, Pages 65–69
Authors
, , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us