Li Chenxing, Feng Jianquan, Liu Zuquan, Xu Menghan, Feng Jie, Du Ding
Department of Chemistry, School of Science, China Pharmaceutical University, Nanjing, 210009, P.R. China.
Angew Chem Int Ed Engl. 2025 Aug 11;64(33):e202508789. doi: 10.1002/anie.202508789. Epub 2025 Jun 17.
Helicenoids have attracted considerable interest in diverse research areas owing to their unique structural and electronic characteristics. However, catalytic asymmetric synthesis of helically chiral molecules has remained a formidable challenge. In particular, the organocatalytic enantioselective construction of heterohelicenoids has witnessed fairly limited progress, presumably due to the lack of rational design of competent substrates, the right choice of suitable reactions, and highly effective catalytic systems. In this study, we report the helicoselective and divergent synthesis of a new class of pyran-2-one-fused [5]helicenoids and [4]helicenoids through an NHC organocatalytic step-economical (3+3) annulation reaction. The protocol features broad substrate scope, ease of late-stage functionalization, and excellent stereo-control with enantioselectivities up to >99%. Moreover, the optical properties of the synthesized oxohelicenoids and their derivatives were characterized to explore their potential applications in material sciences.
由于其独特的结构和电子特性，螺旋烯类化合物在不同的研究领域引起了相当大的关注。然而，螺旋手性分子的催化不对称合成仍然是一个巨大的挑战。特别是，杂螺旋烯类化合物的有机催化对映选择性构建进展相当有限，这可能是由于缺乏对合适底物的合理设计、合适反应的正确选择以及高效的催化体系。在本研究中，我们报道了通过氮杂环卡宾有机催化的原子经济性（3+3）环化反应，对一类新型的吡喃-2-酮稠合[5]螺旋烯类化合物和[4]螺旋烯类化合物进行螺旋选择性和发散性合成。该方法具有底物范围广、易于后期官能团化以及出色的立体控制等特点，对映选择性高达>99%。此外，对合成的氧代螺旋烯类化合物及其衍生物的光学性质进行了表征，以探索它们在材料科学中的潜在应用。
