循環農業:農業廢棄物高價值化【環工系林坤儀教授】
論文篇名 英文:Catalytic Conversion of a Lignin Model Compound to Value-added Products Using Cu/TEMPO-Catalyzed Aerobic Oxidation
中文:木質素模型化合物通過Cu / TEMPO催化的好氧氧化催化轉化為增值產品
期刊名稱 Biomass Conversion and Biorefinery
發表年份,卷數,起迄頁數 2019, 9, 617-623
作者 JY Lin, KYA Lin
DOI 10.1007/s13399-019-00384-7
中文摘要 通常使用過渡金屬和不可回收的H2O2作為氧化劑,將木質素模型化合物香草醇(VAL)催化氧化成增值產品香草醛(VN)。在這項研究中,提出了一種替代氧化方法,用於通過將CuI用作催化劑,2,2,6,6-四甲基哌啶1-氧基(TEMPO)作為助催化劑和周圍空氣作為氧氣源,將VAL氧化為VN。該Cu / TEMPO已被證實是將醇氧化為相應醛的高效化學選擇催化方法。與2,2'-聯吡啶(BIPY)/ 1-甲基咪唑(MIM)配位的CuI可以介導TEMPOH和TEMPO之間的環狀氧化轉化,然後將VAL的OH基團氧化為醛基,從而導致VN的形成。此外,溫度的影響似乎是影響VAL氧化的最主要因素。尤其是,VAL的轉化率可以達到99%,在90°C下的選擇性為93%,相應的產量達到了創紀錄的89%,大大高於文獻報導的值。這些特徵表明,Cu / TEMPO催化的好氧氧化確實是將VAL(木質素模型化合物)VAL轉化為目標產品VN的有前途,高度選擇性和有效的手段。
英文摘要 Catalytic oxidation of vanillyl alcohol (VAL), a lignin model compound, to vanillin (VN), a value-added product, is typically implemented using transition metals with non-recyclable H2O2 as an oxidant. In this study, an alternative oxidation process is proposed for VAL oxidation to VN by using CuI as a catalyst, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) as a co-catalyst and ambient air as an oxygen source. This Cu/TEMPO has been validated as a highly effective and chemoselective catalytic process for oxidation of alcohols to corresponding aldehydes. CuI coordinated with 2,2′-bipyridyl (BIPY)/1-methylimidazole (MIM) could mediate the cyclic oxidative transformation between TEMPOH and TEMPO, which then oxidizes the OH group of VAL to an aldehyde group, leading to the formation of VN. In addition, the effect of temperature seems as the most influencing factor for VAL oxidation. In particular, the conversion of VAL can reach 99% with a high selectivity of 93% at 90 °C, and the corresponding production is the record-high value of 89%, tremendously higher than the reported values in the literature. These features indicate that Cu/TEMPO-catalyzed aerobic oxidation is indeed a promising, highly selective, and efficient means for valorization of VAL, the lignin model compound, to the target product, VN.