Naturally occurring chlorophylls are important substances in the photosynthesis of higher plants.Their asymmetric carbon skeleton structures, the aromatic macrocyclic chromophores and the various active substituted groups attached to the periphery form a class of special natural products.The different chlorophullous degradation products have also been applied as photosensitizers in the area of photodynamic therapy (PDT), dye-sensitized solar cells (DSSCs) and artificial photosynthetic reaction centers.The diverse types of aromatic πr-systems, the multi-region active reaction sites and the complicated tautomeric structures of the chlorophyllous macrocyclic molecules form their characteristic chemical properties.The close-relevance of the pyrrol subring with the azaannulene in chlorophyll and the efficient conjugation of peripheric functional groups with mother cyclic delocalized system lead to that the different rearrangements frequently occur in chlorophyllous chlorins.The reaction scopes involve each pyrrol subring, the bridged meso-position and the combined exocyclic ring.The rearrangements, either including common name reaction or revealing unique transannular rearrangement, adequately reflect the universality in rearranged form and the novelty in reaction process.These special chemical conversions have been efficient approaches for designing and establishing macrocyclic compounds with novel carbon framework and practical application prospect, and are also an important entry point to deeply explore the basic theory, chemical synthesis and applications research of chlorophyll.Therefore, the recent rearrangement reactions about chlorophyllous tetrapyrrol molecules, based on their chemical modifications and structural conversions are reviewed.%广泛存在于自然界的叶绿素是高等植物进行光合作用的重要物质,它们的非对称性碳架结构、芳香性大环色基和连带的各种取代基团形成了一类特殊的天然产物,其不同的降解产物在光动力治疗、染料敏化太阳能电池和人工光合成等诸多领域得以广泛应用.叶绿素类大环分子中不同类型的芳香性π-体系、多区域的活性反应位点以及复杂的互变结构形成其独有的化学性质,叶绿素中的吡咯子环和氮杂轮烯结构的密切关联以及环上官能基团与母环离域体系的有效共轭,导致叶绿素类二氢卟吩经常发生各种重排反应,从不同的层面上充分地体现出重排类型的广泛性和反应历程的新颖性.这些特殊的化学转换一直是设计和构建具有新颖碳架结构和实际应用前景的大环化合物的有效途径,也是深入探讨叶绿素的基础理论、化学合成以及应用研究的重要切入点.为此,本文基于该类天然产物的化学修饰和结构转换,综述了近期叶绿素类四吡咯大环分子的重排反应研究.
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