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Published on: August 16, 2018
Calcium(II)-Catalyzed Three-Component Alkoxyselenation of Allenes with Selenium-Nitrogen Exchange (SeNEx) Reagents
Zhiqiang Duan1, Jie Liu1, Qiudi Wu1
1Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, China.
None:
A calcium-catalyzed three-component alkoxyselenation of allenes using selenium-nitrogen exchange (SeNEx) reagents and alcohols has been developed. Under mild conditions, this transformation enables direct and efficient access to structurally diverse organoselenium compounds through simultaneous formation of C-Se and C-O bonds. The reaction exhibits broad substrate scope and good functional-group tolerance, accommodating a range of aryl-, heteroaryl-, sterically demanding, and alkyl-substituted allenes, as well as diverse benzothiaselenazole 1-oxides, ebselen, and several alcohol nucleophiles. Excellent chemo- and regioselectivity are observed throughout. Gram-scale experiments demonstrate the practicality of the protocol, while control experiments argue against a radical pathway. This work provides a practical calcium-catalyzed SeNEx approach for allene selenofunctionalization, enabling direct access to structurally enriched organoselenium scaffolds.
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