近年来, 甲磺酰化反应受到有机合成工作者的广泛关注, 并取得了重要的发展, 甲磺酰基的来源主要包括: (1)甲磺酰氯; (2)甲基亚磺酸盐; (3)二甲基亚砜; (4)亚硫酸二甲酯; (5)二氧化硫和甲基源原位结合. 甲磺酰化反应可以通过无过渡金属催化、过渡金属催化、光催化、电催化等手段来实现. 本文综述了近几年来甲磺酰化反应在有机合成领域的应用的研究进展, 重点阐述了通过光催化及电催化的自由基型甲磺酰化反应.

In recent years, organic reactions involving mesylation have attracted the attention of organic chemists and have made great progress. The sources of methylsulfonyl group mainly include: (1) methylsulfonyl chloride; (2) methylsulfinate salts; (3) dimethyl sulfoxide; (4) dimethyl sulfite; (5) SO₂ and methyl sources in situ generating. Mesylation can be achieved by means of transition-metal-free catalysis, transition metal catalysis, photocatalysis, electrocatalysis, etc. In this review, the applications of mesylation in recent years are summarized. The photocatalysis or electrocatalysis of radical methylsulfonation are emphasized. Additionally, mesylation reactions have been aroused considerable interests both from methylsulfonyl structural standpoint and its application in drugs. Given the increasing application of methylsulfonyl group in the development of drugs and unarguable importance of methylsulfonyl compounds in medicinal chemistry and agrochemistry, it is no doubt that the methylsulfonyl skeleton is a bioactive molecule and is currently in the “emerging mesylation motifs”. Although the synthesis and application of structurally diverse methylsulfonyl compounds have been witnessed in the past decade, the most widely used methods for the preparation of these compounds include all kinds of modern techniques with various methylsulfonyl reagent, which can be generated from various kinds of precursors. For the transition metal-catalyzed synthesis of methylsulfonyl compounds, some common metal salts (such as copper, copper, palladium, iron, nickel) are used as catalysts. Moreover, the visible-light synergistic transition metal catalysis strategy is a simple and efficient method for the construction of methylsulfonyl compounds, and the asymmetric synthesis of methylsulfonyl compounds can be achieved in the presence of chiral ligands. In multi-component reactions, SO₂-insertion has some advantages that cannot be achieved by traditional mesylated reagents for the direct mesylation of alkenes or alkynes. Despite the remarkable achievements in the synthesis of methylsulfonyl compounds, there are still many issues that need to be addressed. For instance, multi-component mesylation reactions are rarely applied in electrocatalysis, asymmetric catalysis fields and flow chemistry. Hopefully, mesylation can gradually appear in photo- and electro-catalyzed radical chemistry, and the related asymmetric reactions will also get more attention and development in the near future.