resumo
A positively charged lamellar coordination polymer based on a flexible triphosphonic acid linker is reported. [Gd(H(4)nmp)(H2O)(2)]Cl center dot 2H(2)O (1) [H(6)nmp=nitrilotris(methylene-phosphonic acid)] was obtained by a one-pot approach by using water as a green solvent and by forcing the inclusion of additional acid sites by employing HCl in the synthesis. Compound 1 acts as a versatile heterogeneous acid catalyst with outstanding activity in organic reactions such as alcoholysis of styrene oxide, acetalization of benzaldehyde and cyclohexanaldehyde and ketalization of cyclohexanone. For all reaction systems, very high conversions were reached (92-97%) in only 15-30 min under mild conditions (35 degrees C, atmospheric pressure). The coordination polymer exhibits a protonic conductivity of 1.23 x 10(-5) Scm(-1) at 98% relative humidity and 40 degrees C.
palavras-chave
METAL-ORGANIC FRAMEWORKS; ONE-POT ACETALIZATION; EFFICIENT ACETALIZATION; HETEROGENEOUS CATALYSTS; PROTON CONDUCTIVITY; LINKER SUBSTITUTION; MAGNETIC-PROPERTIES; DIMETHYL ACETALS; LEWIS ACIDITY; Y ZEOLITES
categoria
Chemistry
autores
Mendes, RF; Antunes, MM; Silva, P; Barbosa, P; Figueiredo, F; Linden, A; Rocha, J; Valente, AA; Paz, FAA
nossos autores
Anabela Tavares Aguiar Valente
Investigador Principal
Filipe Alexandre Almeida Paz
Investigador Principal
Filipe Miguel H Lebre R Figueiredo
Investigador Principal
João Rocha
Prof. Catedrático
Maria Margarida Feitor Pintão Moreno Antunes
Investigador Júnior
Patrícia Rodrigues da Silva
Bolseiro de investigação
Paula Cristina Vieira Barbosa
Investigador Auxiliar
Ricardo Faria Mendes
Investigador JúniorGrupos
G1 - Materiais Porosos e Nanossistemas
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
G4 - Materiais Renováveis e Economia Circular
agradecimentos
Funding agencies and projects: We wish to thank Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), the European Union, QREN, FEDER through Programa Operacional Factores de Competitividade (COMPETE) and CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. We also thank FCT for funding the R&D project FCOMP-01-0124-FEDER-041282 (Ref. FCT EXPL/CTM-NAN/0013/2013). Individual grants and scholarships: FCT is also gratefully acknowledged for the Ph.D. grants Nos. SFRH/BD/84231/2012 and SFRH/BD/46601/2008 (to R.F.M. and P.S., respectively), the post-doctoral grants Nos. SFRH/BPD/89068/2012 and SFRH/BPD/96665/2013 (to M.M.A. and P.B., respectively), and the Development grant No. IF/01174/2013 (to F.F.).