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Title: Repercussions of multi-electron uptake by a twistacene: a reduction-induced double dehydrogenative annulation
Chemical reduction of highly-twisted 9,10,11,20,21,22-hexaphenyltetrabenzo[a,c,l,n]pentacene (C74H46, 1) was investigated using Li and Cs metals as the reducing agents. The Cs-induced reduction of 1 in the presence of 18-crown-6 ether enabled the isolation of a solvent-separated ion pair (SSIP) with a “naked” monoanion. Upon reduction with Li metal, a double reductive dehydrogenative annulation of 1 was observed to afford a new C74H422– dianion. The latter was shown to undergo a further reduction to C74H424– without additional core transformation. All products were characterized by single-crystal X-ray diffraction and spectroscopic methods. Subsequent in-depth theoretical analysis of one vs. two and four electron uptake by 1 provided insights into how the changes of geometry, aromaticity and charge facilitated the core transformation of twistacene observed upon two-fold reduction. These experimental and theoretical results pave the way to understanding of the reduction-induced core transformations of highly twisted and strained π-systems.  more » « less
Award ID(s):
2003411 1834750
PAR ID:
10491569
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
RSC
Date Published:
Journal Name:
Organic Chemistry Frontiers
Volume:
10
Issue:
23
ISSN:
2052-4129
Page Range / eLocation ID:
5823 to 5833
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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