Dehydrogenative desaturation-relay via formation of multicenter-stabilized radical intermediates. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Shang, Yaping; Jie, Xiaoming; Jonnada, Krishna; Zafar, Syeda; Su, Weiping
• Is Part Of: Nature communications. Volume 8:Issue 1(2017)
• Page Start: 1
• Page End: 8
• Publication Date: 2017-12
• Subjects: Biology -- Periodicals; Physical sciences -- Periodicals; 505
• DOI: 10.1038/s41467-017-02381-8
• Languages: English
• ISSNs: 2041-1723

Abstract

Abstract In organic molecules, the reactivity at the carbon atom next to the functional group is dramatically different from that at other carbon atoms. Herein, we report that a versatile copper-catalyzed method enables successive dehydrogenation or dehydrogenation of ketones, aldehydes, alcohols, α, β-unsaturated diesters, andN -heterocycles to furnish stereodefined conjugated dienecarbonyls, polyenecarbonyls, and nitrogen-containing heteroarenes. On the basis of mechanistic studies, the copper-catalyzed successive dehydrogenation process proceeds via the initial α, β-desaturation followed by further dehydrogenative desaturation of the resultant enone intermediate, demonstrating that the reactivity at α-carbon is transferred through carbon–carbon double bond or longer π-system to the carbon atoms at the positions γ, ε, and η to carbonyl groups. The dehydrogenative desaturation–relay is ascribed to the formation of an unusual radical intermediate stabilized by 5- or 7, - or 9-center π-systems. The discovery of successive dehydrogenation may open the door to functionalizations of the positions distant from functional groups in organic molecules. Synthesis of valuable polyene molecules under mild conditions and with good functional groups tolerance is of paramount importance. Here, the authors show the versatile copper-catalyzed successive dehydrogenation of a variety of organic substrates affording highly conjugated unsaturated products.