Novel polystyrene-immobilized chiral amino alcohols as heterogeneous ligands for the enantioselective arylation of aldehydes in batch and continuous flow regime

Author(s)

Forni, Jose Augusto ; Toneto Novaes, Luiz Fernando ; Galaverna, Renan ; Pastre, Julio C.

• Document type: Journal article
• Source: CATALYSIS TODAY; v. 308, p. 8-pg., 2018-06-15.

Abstract

Six different ligands derived from (S)-proline, (2S,4R)-4-hydroxyproline, (S)-tyrosine and (S)-phenylalanine were synthesized and screened in homogeneous phase for the enantioselective arylation of aldehydes using mixed organozinc reagents. The best ligands were immobilized on the Merrifield resin and evaluated in batch and continuous flow regimes. In batch, up to 89% yield and 90:10 enantiomeric ratio were obtained. In continuous flow regime, we explored the examples that were more challenging in batch, being able to obtain the desired product in 88% yield and 94:6 of enantiomeric ratio in residence time as low as 1.5 min. (AU)

• FAPESP's process: 15/08199-6 - Application of Dioxiranes in continuous flow, synthesis of Actinoranone and decalin fragment of Azadirachtin
• Grantee: Luiz Fernando Toneto Novaes
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/26378-2 - Development of methodologies and synthetic processes employing a new technological platform: micro and meso reactor assisted synthesis of natural products and derivatives with potential pharmacological activity
• Grantee: Júlio Cezar Pastre
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 14/25770-6 - New frontiers in cross-coupling reactions promoted by palladium: combining enantioselective catalysis, C-H activations, new materials and in flux reactions aiming at high efficiency and sustainability in synthetic processes
• Grantee: Carlos Roque Duarte Correia
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/26093-8 - Development of catalysts immobilized in carbon nanotubes and evaluation of their performance in continuous flow
• Grantee: José Augusto Forni
• Support Opportunities: Scholarships in Brazil - Master