Andreetta Philip, Martin Robert T, Souilah Charafa, Rentería-Gómez Ángel, Song Zhihui, Khorramshahi Bayat Yas, Ivlev Sergei, Gutierrez Osvaldo, Casitas Alicia
Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043, Marburg, Germany.
Department of Chemistry and Biochemistry, University of Maryland, College Park. 8051 Regents Dr, College Park, Maryland, 20742, USA.
Angew Chem Int Ed Engl. 2023 Nov 13;62(46):e202310129. doi: 10.1002/anie.202310129. Epub 2023 Oct 13.
Here, we report the development of cobalt(I)-catalyzed regioselective allylic alkylation reactions of tertiary allyl carbonates with 1,3-dicarbonyl compounds. A family of well-defined tetrahedral cobalt(I) complexes bearing commercially available bidentate bis(phosphine) ligands [(P,P)Co(PPh )Cl] are synthesized and explored as catalysts in allylic alkylation reactions. The catalyst [(dppp)Co(PPh )Cl] (dppp=1,3-Bis(diphenylphosphino)propane) enables the alkylation of a large variety of tertiary allyl carbonates with high yields and excellent regioselectivity for the branched product. Remarkably, this methodology is selective for the activation of tertiary allyl carbonates even in the presence of secondary allyl carbonates. This contrasts with the selectivity observed in cobalt-catalyzed allylic alkylations enabled by visible light photocatalysis. Mechanistic insights by means of experimental and computational investigations support a Co(I)/Co(III) catalytic cycle.
在此，我们报道了钴（I）催化叔碳酸烯丙酯与1,3 - 二羰基化合物的区域选择性烯丙基烷基化反应的进展。合成了一系列带有市售双齿双（膦）配体[（P,P）Co（PPh ）Cl]的结构明确的四面体钴（I）配合物，并将其作为烯丙基烷基化反应的催化剂进行研究。催化剂[（dppp）Co（PPh ）Cl]（dppp = 1,3 - 双（二苯基膦基）丙烷）能够使多种叔碳酸烯丙酯发生烷基化反应，对支链产物具有高收率和优异的区域选择性。值得注意的是，即使存在仲碳酸烯丙酯，该方法对叔碳酸烯丙酯的活化仍具有选择性。这与可见光光催化实现的钴催化烯丙基烷基化反应中观察到的选择性形成对比。通过实验和计算研究获得的机理见解支持了Co（I）/Co（III）催化循环。
