Bołt Małgorzata, Delaude Lionel, Żak Patrycja
Department of Organometallic Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznan, Umultowska 89B, 61-614 Poznan, Poland.
Laboratory of Organometallic Chemistry and Homogeneous Catalysis, Institut de Chimie Organique (B6a), Allée du six août 13, Quartier Agora, Université de Liège, 4000 Liège, Belgium.
Dalton Trans. 2022 Mar 15;51(11):4429-4434. doi: 10.1039/d2dt00243d.
Eight rhodium complexes-including four new compounds-with the generic formula [RhCl(cod)(NHC)] (cod is 1,3-cyclooctadiene) differing by the size of their N-heterocyclic carbene (NHC) ligand were prepared, characterized, and found to be catalytically active in the hydrothiolation of terminal alkynes with aliphatic or aromatic thiols. The steric bulk of the carbene was found to markedly influence the reaction rate and selectivity. In particular, superbulky NHCs led to the almost quantitative formation of the sole α-vinyl sulfide products. The experimental conditions were optimized to allow the straightforward synthesis of a broad range of mono- and disubstituted α-adducts starting from terminal alkynes (18 examples) and thiols (5 examples). Altogether, the procedure devised in this study provides an easy access to α-vinyl sulfides with full atom economy and a low catalyst loading.
制备并表征了八种铑配合物，包括四种新化合物，其通式为[RhCl(cod)(NHC)]（cod为1,3 - 环辛二烯），它们的N - 杂环卡宾（NHC）配体大小不同，并且发现这些配合物在末端炔烃与脂肪族或芳香族硫醇的氢硫基化反应中具有催化活性。发现卡宾的空间位阻对反应速率和选择性有显著影响。特别是，超大位阻的NHC导致几乎定量地形成单一的α - 乙烯基硫醚产物。优化了实验条件，以便从末端炔烃（18个例子）和硫醇（5个例子）直接合成多种单取代和双取代的α - 加合物。总之，本研究设计的方法提供了一种以全原子经济性和低催化剂负载量轻松制备α - 乙烯基硫醚的途径。
