A PMMA-based heterogeneous photocatalyst for visible light-promoted [4+2] cycloaddition
A PMMA-based heterogeneous photocatalyst for visible light-promoted [4+2] cycloaddition
复制标题
DOI：
10.1039/d0cy00016g
复制
发表时间：
2020-04-07
影响因子：
5
通讯作者：
Zhang, Kai A. I.
中科院分区：
文献类型：
--
作者：
Huber, Niklas;Li, Run;Zhang, Kai A. I.
由完全共轭网络组成的大分子有机光催化剂在可见光促进的光氧化还原催化中具有广阔的应用前景。精确的复制和精确的共轭长度控制仍然是全共轭和大分子光催化剂的一个重要挑战。在这里，我们介绍了一种基于经典PMMA的光催化材料，该材料具有定义的电子给体和受体单元，具有精确可控的氧化还原电位和共轭长度，创造了一类有前途的无金属、稳定和低成本的多相光催化剂。此外，PMMA共聚物基质在有机溶剂中的溶胀导致了基质扩散的增强，从而提高了催化效率。在空气中光催化[4+2]环加成反应具有较高的效率和选择性，光催化剂载量较低。PMMA光催化剂的光催化效率可与最先进的金属或非金属催化剂相媲美，同时便于回收。
Macromolecular organic photocatalysts consisting of a completely conjugated network have broad and promising applications in visible light-promoted photoredox catalysis. Precise reproduction and control of exact conjugation length remains an important challenge for fully conjugated and macromolecular photocatalysts. Here, we introduce a new photocatalytic material based on classical PMMA copolymerised with defined electron donor and acceptor units with precisely controllable redox potential and conjugation length, creating a promising class of metal-free, stable and low-cost heterogeneous photocatalysts. Furthermore, swelling of the PMMA copolymer matrix in organic solvents led to enhanced substrate diffusion and thereby increased catalytic efficiency. High efficiency and selectivity was achieved for photocatalytic [4 + 2] cycloaddition reactions in air with low effective photocatalyst loading. The photocatalytic efficiency of the PMMA photocatalyst was comparable with the state-of-the-art metal or non-metal catalysts while facilitating easy recyclability.