Bhawana Devi, Senthil Murugan Arumugam, Ravi Kumar Kunchala, Paramdeep Kaur, Sangeeta Mahala and Sasikumar Elumalai
{"title":"Molybdenum oxide with a varied valency ratio to enable selective d-galactose epimerization to d-talose†","authors":"Bhawana Devi, Senthil Murugan Arumugam, Ravi Kumar Kunchala, Paramdeep Kaur, Sangeeta Mahala and Sasikumar Elumalai","doi":"10.1039/D4RE00076E","DOIUrl":null,"url":null,"abstract":"<p >\r\n <small>D</small>-Talose, classified as a rare and expensive sugar molecule, is gaining attraction due to its antimicrobial and anti-inflammatory properties. Its production is widely investigated by adopting biological enzymes, which is costly. However, alternative chemical methodologies have reported its formation as a side product and in minor amounts. We report for the first time its significant synthesis using <small>D</small>-galactose (which comprises whey and hemicellulose) by employing a finely tuned molybdenum oxide (MoO<small><sub>3</sub></small>) solid acid catalyst. The nitric acid treatment of MoO<small><sub>3</sub></small> modulated the valency ratio in Mo species (Mo<small><sup>5+/6+</sup></small>), resulting in an improved Lewis acidity with up to 199 μmol g<small><sup>−1</sup></small> acidic sites and porosity of up to 48% relative to the pristine MoO<small><sub>3</sub></small>, attributed to the generated oxygen vacancies. Combined together these have assisted in an augmented <small>D</small>-talose synthesis with as high as 25% yield, 70% selectivity and 98% carbon balance in a water medium under modest reaction conditions (120 °C and 30 min). As proposed, Mo's interaction with <small>D</small>-galactose to form a Mo–sugar complex has influenced the C1–C2 carbon shift to yield <small>D</small>-talose. Furthermore, the typical isotopic labelling NMR characterization has confirmed the Bílik mechanism of C2-galactose epimerization. Overall, the heterogeneous catalytic setup represents a sustainable and feasible method for producing rare sugar for food additive and pharma applications.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 9","pages":" 2293-2305"},"PeriodicalIF":3.4000,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Reaction Chemistry & Engineering","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/re/d4re00076e","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
D-Talose, classified as a rare and expensive sugar molecule, is gaining attraction due to its antimicrobial and anti-inflammatory properties. Its production is widely investigated by adopting biological enzymes, which is costly. However, alternative chemical methodologies have reported its formation as a side product and in minor amounts. We report for the first time its significant synthesis using D-galactose (which comprises whey and hemicellulose) by employing a finely tuned molybdenum oxide (MoO3) solid acid catalyst. The nitric acid treatment of MoO3 modulated the valency ratio in Mo species (Mo5+/6+), resulting in an improved Lewis acidity with up to 199 μmol g−1 acidic sites and porosity of up to 48% relative to the pristine MoO3, attributed to the generated oxygen vacancies. Combined together these have assisted in an augmented D-talose synthesis with as high as 25% yield, 70% selectivity and 98% carbon balance in a water medium under modest reaction conditions (120 °C and 30 min). As proposed, Mo's interaction with D-galactose to form a Mo–sugar complex has influenced the C1–C2 carbon shift to yield D-talose. Furthermore, the typical isotopic labelling NMR characterization has confirmed the Bílik mechanism of C2-galactose epimerization. Overall, the heterogeneous catalytic setup represents a sustainable and feasible method for producing rare sugar for food additive and pharma applications.
期刊介绍:
Reaction Chemistry & Engineering is a new journal reporting cutting edge research into all aspects of making molecules for the benefit of fundamental research, applied processes and wider society.
From fundamental, molecular-level chemistry to large scale chemical production, Reaction Chemistry & Engineering brings together communities of chemists and chemical engineers working to ensure the crucial role of reaction chemistry in today’s world.