Synthesis and structural characterization of phenylalanine-based Co(II) and Cd(II) 1D coordination polymers and their use as efficient catalysts 3 for aerobic oxidation of cycloalkenes

FEDERICO MOVILLA; JUAN MANUEL REY; LUIS SANTIBAÑEZ; EVGENIA SPODINE; PATRICIO CANCINO; FLORENCIA DI SALVO

Congreso; ACS - SPRING MEETING; 2021

In recent years,the research of Coordination Polymers (CPs) is undergoing an enormous growthsince they exhibit diverse structural architectures, known spatialconfigurations and high specificity regarding the adsorption and interactionwith guest molecules. Among a wide variety of applications, catalysis is one ofthe most frequently explored. Amino acids are widely recognized as a versatileligand class in organometallic and coordination chemistry catalysis. As anN,O-bidentate donor, amino acid-based ligands have considerable effects on thestereoelectronic nature of the resultant metal complex, providing the frameworkfor the development of highly selective processes. Besides, due to thedifferent coordination modes, amino acid-based ligands are also useful buildingblocks for the obtaining of biocompatible and chiral CPs. Herein, we present the synthesis and structuralcharacterization of two new Co(II) (1) and Cd(II) (2) 1D CPs,derived from the biologically relevant aldehyde piperonal and the amino acidL-Phenylalanine (Figure). In addition, their use as catalyst for theheterogenous aerobic oxidation of cycloalkenes is also explored. Theirstructures were determined by single crystal X-ray diffraction experiments inthe solid state and different spectroscopies in solution. Thermal studies showgreat responses, demonstrated their stability. The catalytic results show thatboth catalysts are active in the oxidation of cyclohexene achieving aconversion of 75% at 75°C, being cycloxenone the main product, indicating a 68%of selectivity. A remarkable result is that, the polymer based on Co(II) demonstratedto be also effective at room temperature (50% of conversion and 70% of selectivity).   @font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:swiss;mso-font-pitch:variable;mso-font-signature:-536859905 -1073732485 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:0cm;line-height:107%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-size:11.0pt;mso-ansi-font-size:11.0pt;mso-bidi-font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;}.MsoPapDefault{mso-style-type:export-only;margin-bottom:8.0pt;line-height:107%;}div.WordSection1{page:WordSection1;}