Kitanosono Taku, Kobayashi Shū
Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Chemistry. 2020 Aug 3;26(43):9408-9429. doi: 10.1002/chem.201905482. Epub 2020 Jun 5.
Ever-evolving catalyst advances in synthetic protocols using water as a reaction medium have enriched the understanding of sustainable organic chemistry. Because conventional classification and definitions were ambivalent, it is proposed here that catalytic reactions using water be collectively called to be "in water", with further classification into seven types. When accelerated in water as heterogeneous mixtures, the reactions can be regarded as following an "on-water" mechanism. The original term "on water" coined by Sharpless is incongruous with catalytic reactions, whereas on-water used in this review covers all the interfaces involving water where chemical reactions are accelerated. As a result of the unconcluded dispute on the antiquated catalyst-free "on water" model, the modified model defines three water layers: water molecules that are oriented to extrude protons toward the oil phase in the inner layer, those enwrapped by a secondary layer, and finally the bulk water layer. In light of the latitudinous outlook on the role of water at the interface, selected examples of reactions, in particular those reported over the past decade, that follow an "on-water" mechanism are reviewed herein.
在以水为反应介质的合成方法中，不断发展的催化剂进展丰富了对可持续有机化学的理解。由于传统的分类和定义含糊不清，本文提出将使用水的催化反应统称为“在水中”，并进一步分为七种类型。当在水作为非均相混合物中加速时，这些反应可被视为遵循“水相上”机制。夏普莱斯提出的原始术语“水相上”与催化反应不一致，而本综述中使用的水相上涵盖了所有涉及水且化学反应加速的界面。由于对过时的无催化剂“水相上”模型存在未解决的争议，改进后的模型定义了三个水层：在内层中向油相挤出质子的取向水分子、被第二层包裹的水分子，以及最后的本体水层。鉴于对界面处水的作用的广泛观点，本文综述了遵循“水相上”机制的选定反应实例，特别是过去十年报道的那些实例。
