Chemodivergent and Enantioselective Synthesis of Spirobi[dihydrophenalene] Structures
Chuanyong Peng, Chenhong Wang, Changhui Wu, Junhao Xing, Fei Xue, Xiaowei Dou
Abstract
The development and enantioselective synthesis of two types of C 2 -symmetric spirobi[dihydrophenalene] structures is reported. The reaction proceeds via rhodium-catalyzed 2-fold asymmetric conjugate arylation of dienones followed by BF 3 ·OEt 2 -promoted spirocyclization to give the enantiopure spiro products. Additive-dependent chemodivergent synthesis of 3,3′-diarylated 2,2′,3,3′-tetrahydro-1,1′-spirobi[phenalene]-9,9′-diols (3,3′-Ar 2 -SPHENOLs) and the corresponding spiro diary ethers from the same intermediate is achieved. The structural properties of 3,3′-Ph 2 -SPHENOL are analyzed, and its application in asymmetric catalysis has been preliminarily demonstrated.