Synthesis, characterisation and application of pyridine-modified chitosan derivatives for the first non-racemic Cu-catalysed Henry reaction

Fernanda Jorge Goncalves; Fadwa Kamal; Anne Gaucher; Richard Gil; Flavien Bourdreux; Charlotte Martineau-Corcos; Leandro Vinícius Alves Gurgel; Laurent Frédéric Gil; Damien Prim

doi:10.1016/j.carbpol.2017.12.012

Synthesis, characterisation and application of pyridine-modified chitosan derivatives for the first non-racemic Cu-catalysed Henry reaction

Carbohydr Polym. 2018 Feb 1:181:1206-1212. doi: 10.1016/j.carbpol.2017.12.012. Epub 2017 Dec 6.

Authors

Fernanda Jorge Goncalves¹, Fadwa Kamal², Anne Gaucher², Richard Gil³, Flavien Bourdreux², Charlotte Martineau-Corcos², Leandro Vinícius Alves Gurgel¹, Laurent Frédéric Gil⁴, Damien Prim⁵

Affiliations

¹ Grupo de Química Orgânica Ambiental, Departamento de Química, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro de Cruzeiro, 35400-000 Ouro Preto, Minas Gerais, Brazil.
² University of Versailles St-Quentin-en-Yvelines, Institut Lavoisier de Versailles UMR CNRS 8180, 45, Avenue des Etats-Unis, 78035 Versailles, France.
³ University Paris-Sud, ICMMO, UMR CNRS 8182, 91405 Orsay, France.
⁴ Grupo de Química Orgânica Ambiental, Departamento de Química, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro de Cruzeiro, 35400-000 Ouro Preto, Minas Gerais, Brazil. Electronic address: laurent@iceb.ufop.br.
⁵ University of Versailles St-Quentin-en-Yvelines, Institut Lavoisier de Versailles UMR CNRS 8180, 45, Avenue des Etats-Unis, 78035 Versailles, France. Electronic address: damien.prim@uvsq.fr.

PMID: 29253950
DOI: 10.1016/j.carbpol.2017.12.012

Abstract

The preparation, characterisation and application of two pyridine-modified chitosan derivatives (C1 and C2) containing Cu(OAc)₂ adsorbed as catalysts for the conversion of benzaldehyde into 2-nitro-1-phenylethanol are described. Quantitative solid-state ¹³C multiple-contact cross-polarization, magic-angle-spinning, nuclear magnetic resonance (MC-CP MAS NMR) measurements confirmed the successful grafting of 2-pyridinecarboxaldehyde and 6-methylpyridine-2-carboxaldehyde to the chitosan backbone and indicated that 47(±2)% of the NH₂ groups were grafted for both C1 and C2. The use of C1-Cu(OAc)₂ as a catalyst in the nitroaldol reaction led to 96(±1)% conversion and 19(±4)% enantiomeric excess (ee), while the use of C2-Cu(OAc)₂ as a catalyst also promoted the nitroaldol reaction, affording almost quantitatively the expected 2-nitro-1-phenylethanol (98(±1)%) with 14.5(±1.5)% ee.

Keywords: Copper; Henry reaction; Heterogeneous catalysis; Modified chitosan; Solid-state (13)C NMR.