Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study

Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study

Selective oxidation of &#945;-hydroxy esters is one of the most important methods to prepare high value-added &#945;-keto esters. An efficient catalytic system consisting of Zn(NO<sub>3</sub>)<sub>2</sub>/VOC<sub>2</sub>O<sub>4</sub> is reporte...

Full description

Bibliographic Details
Main Authors: Yongwei Ju, Zhongtian Du, Chuhong Xiao, Xingfei Li, Shuang Li
Format: Article
Language:English
Published: MDPI AG 2019-04-01
Series:Molecules
Subjects:
ATR-IR
α-hydroxy esters
α-keto esters
oxidation
zinc nitrate
Online Access:https://www.mdpi.com/1420-3049/24/7/1281
id doaj-d449c4fd48b143f6a968e9178cbf7335
record_format Article
spelling doaj-d449c4fd48b143f6a968e9178cbf73352020-11-24T20:41:56ZengMDPI AGMolecules1420-30492019-04-01247128110.3390/molecules24071281molecules24071281Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR StudyYongwei Ju0Zhongtian Du1Chuhong Xiao2Xingfei Li3Shuang Li4School of Chemical Engineering, Northwest University, Xi’an 710069, ChinaSchool of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, ChinaSchool of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, ChinaSchool of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, ChinaSchool of Chemical Engineering, Northwest University, Xi’an 710069, ChinaSelective oxidation of &#945;-hydroxy esters is one of the most important methods to prepare high value-added &#945;-keto esters. An efficient catalytic system consisting of Zn(NO<sub>3</sub>)<sub>2</sub>/VOC<sub>2</sub>O<sub>4</sub> is reported for catalytic oxidation of &#945;-hydroxy esters with molecular oxygen. Up to 99% conversion of methyl DL-mandelate or methyl lactate could be facilely obtained with high selectivity for its corresponding &#945;-keto ester under mild reaction conditions. Zn(NO<sub>3</sub>)<sub>2</sub> exhibited higher catalytic activity in combination with VOC<sub>2</sub>O<sub>4</sub> compared with Fe(NO<sub>3</sub>)<sub>3</sub> and different nitric oxidative gases were detected by situ attenuated total reflection infrared (ATR-IR) spectroscopy. UV-vis and ATR-IR results indicated that coordination complex formed in Zn(NO<sub>3</sub>)<sub>2</sub> in CH<sub>3</sub>CN solution was quite different from Fe(NO<sub>3</sub>)<sub>3</sub>; it is proposed that the charge-transfer from Zn<sup>2+</sup> to coordinated nitrate groups might account for the generation of different nitric oxidative gases. The XPS result indicate that nitric oxidative gas derived from the interaction of Zn(NO<sub>3</sub>)<sub>2</sub> with VOC<sub>2</sub>O<sub>4</sub> could be in favor of oxidizing VOC<sub>2</sub>O<sub>4</sub> to generate active vanadium (V) species. It might account for different catalytic activity of Zn(NO<sub>3</sub>)<sub>2</sub> or Fe(NO<sub>3</sub>)<sub>3</sub> combined with VOC<sub>2</sub>O<sub>4</sub>. This work contributes to further development of efficient aerobic oxidation under mild reaction conditions.https://www.mdpi.com/1420-3049/24/7/1281ATR-IRα-hydroxy estersα-keto estersoxidationzinc nitrate
collection DOAJ
language English
format Article
sources DOAJ
author Yongwei Ju
Zhongtian Du
Chuhong Xiao
Xingfei Li
Shuang Li
spellingShingle Yongwei Ju
Zhongtian Du
Chuhong Xiao
Xingfei Li
Shuang Li
Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
Molecules
ATR-IR
α-hydroxy esters
α-keto esters
oxidation
zinc nitrate
author_facet Yongwei Ju
Zhongtian Du
Chuhong Xiao
Xingfei Li
Shuang Li
author_sort Yongwei Ju
title Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
title_short Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
title_full Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
title_fullStr Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
title_full_unstemmed Novel Effect of Zinc Nitrate/Vanadyl Oxalate for Selective Catalytic Oxidation of α-Hydroxy Esters to α-Keto Esters with Molecular Oxygen: An In Situ ATR-IR Study
title_sort novel effect of zinc nitrate/vanadyl oxalate for selective catalytic oxidation of α-hydroxy esters to α-keto esters with molecular oxygen: an in situ atr-ir study
publisher MDPI AG
series Molecules
issn 1420-3049
publishDate 2019-04-01
description Selective oxidation of &#945;-hydroxy esters is one of the most important methods to prepare high value-added &#945;-keto esters. An efficient catalytic system consisting of Zn(NO<sub>3</sub>)<sub>2</sub>/VOC<sub>2</sub>O<sub>4</sub> is reported for catalytic oxidation of &#945;-hydroxy esters with molecular oxygen. Up to 99% conversion of methyl DL-mandelate or methyl lactate could be facilely obtained with high selectivity for its corresponding &#945;-keto ester under mild reaction conditions. Zn(NO<sub>3</sub>)<sub>2</sub> exhibited higher catalytic activity in combination with VOC<sub>2</sub>O<sub>4</sub> compared with Fe(NO<sub>3</sub>)<sub>3</sub> and different nitric oxidative gases were detected by situ attenuated total reflection infrared (ATR-IR) spectroscopy. UV-vis and ATR-IR results indicated that coordination complex formed in Zn(NO<sub>3</sub>)<sub>2</sub> in CH<sub>3</sub>CN solution was quite different from Fe(NO<sub>3</sub>)<sub>3</sub>; it is proposed that the charge-transfer from Zn<sup>2+</sup> to coordinated nitrate groups might account for the generation of different nitric oxidative gases. The XPS result indicate that nitric oxidative gas derived from the interaction of Zn(NO<sub>3</sub>)<sub>2</sub> with VOC<sub>2</sub>O<sub>4</sub> could be in favor of oxidizing VOC<sub>2</sub>O<sub>4</sub> to generate active vanadium (V) species. It might account for different catalytic activity of Zn(NO<sub>3</sub>)<sub>2</sub> or Fe(NO<sub>3</sub>)<sub>3</sub> combined with VOC<sub>2</sub>O<sub>4</sub>. This work contributes to further development of efficient aerobic oxidation under mild reaction conditions.
topic ATR-IR
α-hydroxy esters
α-keto esters
oxidation
zinc nitrate
url https://www.mdpi.com/1420-3049/24/7/1281
work_keys_str_mv AT yongweiju noveleffectofzincnitratevanadyloxalateforselectivecatalyticoxidationofahydroxyesterstoaketoesterswithmolecularoxygenaninsituatrirstudy
AT zhongtiandu noveleffectofzincnitratevanadyloxalateforselectivecatalyticoxidationofahydroxyesterstoaketoesterswithmolecularoxygenaninsituatrirstudy
AT chuhongxiao noveleffectofzincnitratevanadyloxalateforselectivecatalyticoxidationofahydroxyesterstoaketoesterswithmolecularoxygenaninsituatrirstudy
AT xingfeili noveleffectofzincnitratevanadyloxalateforselectivecatalyticoxidationofahydroxyesterstoaketoesterswithmolecularoxygenaninsituatrirstudy
AT shuangli noveleffectofzincnitratevanadyloxalateforselectivecatalyticoxidationofahydroxyesterstoaketoesterswithmolecularoxygenaninsituatrirstudy
_version_ 1716823824491610112

Similar Items