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Title: The contrasting reactivity of trans - vs. cis -azobenzenes (ArNNAr) with benzynes
We report here a study that has revealed two distinct modes of reactivity of azobenzene derivatives (ArNNAr) with benzynes, depending on whether the aryne reacts with a trans - or a cis -azobenzene geometric isomer. Under thermal conditions, trans -azobenzenes engage benzyne via an initial [2 + 2] trapping event, a process analogous to known reactions of benzynes with diarylimines (ArCNAr). This is followed by an electrocyclic ring opening/closing sequence to furnish dihydrophenazine derivatives, subjects of contemporary interest in other fields ( e.g. , electronic and photonic materials). In contrast, when the benzyne is attacked by a cis -azobenzene, formation of aminocarbazole derivatives occurs via an alternative, net (3 + 2) pathway. We have explored these complementary orthogonal processes both experimentally and computationally.  more » « less
Award ID(s):
2155042
NSF-PAR ID:
10463322
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Chemical Science
Volume:
14
Issue:
24
ISSN:
2041-6520
Page Range / eLocation ID:
6730 to 6737
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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