Hexapole [9]Helicene. (12th December 2018)

• Record Type: Journal Article
• Authors: Wang, Yonggen; Yin, Zhibo; Zhu, Yanpeng; Gu, Jiajian; Li, Yang; Wang, Jiaobing
• Is Part Of: Angewandte Chemie. Volume 131:Number 2(2019)
• Page Start: 597
• Page End: 601
• Publication Date: 2018-12-12
• Subjects: Chiralität -- Helicene -- Nichtplanarität -- Sterische Hinderung; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201811706
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Herein we present the first hexapole [9]helicene (H9H ). Co‐catalyzed [2+2+2] cyclotrimerization of a dinaphthopyrene (DNP) functionalized alkyne provides the hexaaryl benzene precursor2, which is transformed intoH9H via a dehydrocyclization reaction. Formation of each embedded [9]helicene involves forging of a new C−C bond, which stitches together two [4]helicene subunits of the neighboring DNP blades, reminiscent of the initial method Martin developed for the preparation of [9]helicene in the 1960s. Single‐crystal X‐ray analysis of both2 andH9H discloses their extremely distorted and crowded structural features. Chiral resolution, optical and electronic properties ofH9H are also presented.