高保护剂回收率的缩醛保护的5-羟甲基糠醛氧化酯化生成2,5-二甲酸呋喃二甲酯,ACS Sustainable Chemistry & Engineering

当前位置： X-MOL 学术 › ACS Sustain. Chem. Eng. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

高保护剂回收率的缩醛保护的5-羟甲基糠醛氧化酯化生成2,5-二甲酸呋喃二甲酯
ACS Sustainable Chemistry & Engineering ( IF 7.1 ) Pub Date : 2023-12-26 , DOI: 10.1021/acssuschemeng.3c06275
Jan J. Wiesfeld ₁ , Ryota Osuga ₁ , Satoshi Suganuma ₁ , Takayuki Aoshima ₂ , Emiel J.M. Hensen ₃ , Kiyotaka Nakajima ₁

Affiliation

聚呋喃酸亚烷基酯是化石基对苯二甲酸酯的重要的有前景的生物基替代品。呋喃酸酯单体可以从生物平台5-羟甲基糠醛（HMF）中获得，但由于其快速低聚，需要在稀溶液中工作，实际应用受到阻碍。在此，我们展示了一种基于用丙烷-1,3-二醇（PDO）对反应性甲酰基进行缩醛化的保护策略，以抑制低聚反应。按照逐步方法，PDO-缩醛化 HMF (PD-HMF) 在 20 wt% 甲醇溶液中氧化酯化，主要生成 PDO-缩醛化 5-甲酰基呋喃-2-甲酸甲酯 (PD-MFFC)，6 中收率达 91.0%使用Au/CeO ₂催化剂在100℃、8MPa空气下加热h 。相对于PD-HMF ，碱的使用量可以减少至7.5mol％Na ₂ CO ₃，这相对于现有技术来说是相当大的进步。在这些改进的条件下，由于氧化降解导致的 PDO 损失限制在 1.4%，这意味着保护剂可以重复使用，这有利于该工艺的经济可行性。PD-MFFC产物流中含有少量MeOH缩醛化的MFFC，可以很容易地脱保护得到MFFC，收率99.1%，PDO回收率93.1%。通过在 20 wt% 甲醇溶液中、在 100 °C、6 MPa 空气下对 MFFC 进行无碱氧化酯化，在 2 小时内，MFFC 可以很容易地转化为 2,5-二甲酸二甲酯 (MFDC)，收率达 96.6%。所提出的逐步方法使用浓缩的 PD-HMF 溶液（20 wt%）将高生产率（MFDC 总产率 >90%）和出色的 PDO 回收率（>91%）结合在一起。

"点击查看英文标题和摘要"

Oxidative Esterification of Acetal-Protected 5-Hydroxymethylfurfural to Dimethyl Furan-2,5-dicarboxylate with High Recovery of Protecting Agent

Polyalkylene furanoates are important prospective biobased substitutes for fossil-based terephthalates. Furanoate monomers can be obtained from the bioplatform 5-hydroxymethylfurfural (HMF), but practical applications are hindered due to its rapid oligomerization, which requires working in dilute solutions. Herein, we demonstrate a protection strategy based on acetalization of the reactive formyl group with propane-1,3-diol (PDO) to suppress oligomerization reactions. Following a stepwise approach, PDO-acetalized HMF (PD-HMF) was oxidatively esterified in a methanolic 20 wt % solution to mainly PDO-acetalized methyl-5-formylfuran-2-carboxylate (PD-MFFC) in a 91.0% yield in 6 h at 100 °C under 8 MPa air using a Au/CeO₂ catalyst. The use of base could be decreased to 7.5 mol % Na₂CO₃ with respect to PD-HMF, which is a considerable advance over the state of the art. The loss of PDO due to oxidative degradation under these improved conditions was limited to 1.4%, implying that the protecting agent could be reused, which benefits the economic viability of the process. The PD-MFFC product stream, which contains a small amount of MeOH-acetalized MFFC, could be easily deprotected to obtain MFFC in a 99.1% yield with a PDO recovery degree of 93.1%. MFFC could readily be converted to dimethyl furan-2,5-dicarboxylate (MFDC) in a 96.6% yield via base-free oxidative esterification of MFFC in a methanolic 20 wt % solution in 2 h at 100 °C under 6 MPa air. The proposed stepwise approach combines high productivity (overall MFDC yield >90%) and excellent PDO recovery (>91%) using concentrated PD-HMF solutions (20 wt %).

更新日期：2023-12-26

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南