An (S)-5-(pyrrolidin-2-yl)-1H-tetrazole organocatalyst has been prepared in the form of a monolithic column through the radical copolymerization of a styryl-functionalized pyrrolidinyl-tetrazole derivative, sty- rene and divinylbenzene in the presence of porogens (dodecanol and toluene). The activity of the mono- lithic pyrrolidinyl-tetrazole organocatalyst (triturated polymer) has been initially tested under batch condi- tions using the asymmetric aldol reaction of cyclohexanone and p-nitrobenzaldehyde as the benchmark. A prerequisite of the study has been the utilization of the eco-friendly water–ethanol mixture as the solvent. After having established the high efficiency and recyclability of the catalyst under these conditions, the effect of the flow regime has been evaluated by fabricating the corresponding monolithic microreactor (pressure-resistant stainless steel column). It has been demonstrated by a brief substrate scope study that the flow regime contributes to preserve the activity of the pyrrolidinyl-tetrazole catalyst over time (5 days on stream) with an almost twofold increase in productivity moving from batch to flow conditions. An added value of the flow procedure has been the optimization of a suitable 2D instrumental setup for simultaneous flow reaction and online flow-injection analysis.

A monolithic 5-(pyrrolidin-2-yl)tetrazole flow microreactor for the asymmetric aldol reaction in water–ethanol solvent

GRECO, Roberto
Primo
;
CACIOLLI, Lorenzo
Secondo
;
ZAGHI, Anna;BORTOLINI, Olga;CAVAZZINI, Alberto;DE RISI, Carmela
Penultimo
;
MASSI, Alessandro
Ultimo
2016

Abstract

An (S)-5-(pyrrolidin-2-yl)-1H-tetrazole organocatalyst has been prepared in the form of a monolithic column through the radical copolymerization of a styryl-functionalized pyrrolidinyl-tetrazole derivative, sty- rene and divinylbenzene in the presence of porogens (dodecanol and toluene). The activity of the mono- lithic pyrrolidinyl-tetrazole organocatalyst (triturated polymer) has been initially tested under batch condi- tions using the asymmetric aldol reaction of cyclohexanone and p-nitrobenzaldehyde as the benchmark. A prerequisite of the study has been the utilization of the eco-friendly water–ethanol mixture as the solvent. After having established the high efficiency and recyclability of the catalyst under these conditions, the effect of the flow regime has been evaluated by fabricating the corresponding monolithic microreactor (pressure-resistant stainless steel column). It has been demonstrated by a brief substrate scope study that the flow regime contributes to preserve the activity of the pyrrolidinyl-tetrazole catalyst over time (5 days on stream) with an almost twofold increase in productivity moving from batch to flow conditions. An added value of the flow procedure has been the optimization of a suitable 2D instrumental setup for simultaneous flow reaction and online flow-injection analysis.
2016
Greco, Roberto; Caciolli, Lorenzo; Zaghi, Anna; Pandoli, Omar; Bortolini, Olga; Cavazzini, Alberto; DE RISI, Carmela; Massi, Alessandro
File in questo prodotto:
File Dimensione Formato  
2016 Reac Chem Eng tetrazole.pdf

solo gestori archivio

Descrizione: Full text ed
Tipologia: Full text (versione editoriale)
Licenza: NON PUBBLICO - Accesso privato/ristretto
Dimensione 1.16 MB
Formato Adobe PDF
1.16 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
11392_2357016_preprint_Massi_Alessandro.pdf

accesso aperto

Descrizione: Pre print
Tipologia: Pre-print
Licenza: PUBBLICO - Pubblico con Copyright
Dimensione 8.31 MB
Formato Adobe PDF
8.31 MB Adobe PDF Visualizza/Apri

I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11392/2357016
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 19
social impact