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"Golden" Cascade Cyclization to Benzo[c]-Phenanthridines.

ABSTRACT: Herein, we describe a gold-catalyzed cascade cyclization of Boc-protected benzylamines bearing two tethered alkyne moieties in a domino reaction initiated by a 6-endo-dig cyclization. The reaction was screened intensively, and the scope was explored, resulting in nine new Boc-protected dihydrobenzo[c]phenanthridines with yields of up to 98 %; even a π-extension and two bidirectional approaches were successful. Furthermore, thermal cleavage of the Boc group and subsequent oxidation gave substituted benzo[c]phenanthridines in up to quantitative yields. Two bidirectional approaches under the optimized conditions were successful, and the resulting π-extended molecules were tested as organic semiconductors in organic thin-film transistors.

SUBMITTER: Hendrich CM

PROVIDER: S-EPMC8597101 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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"Golden" Cascade Cyclization to Benzo[c]-Phenanthridines.

Hendrich Christoph M CM Senn Sebastian S Haas Lea L Hoffmann Marvin T MT Zschieschang Ute U Greiner Luca C LC Rominger Frank F Rudolph Matthias M Klauk Hagen H Dreuw Andreas A Hashmi A Stephen K ASK

Chemistry (Weinheim an der Bergstrasse, Germany) 20210912 59

Herein, we describe a gold-catalyzed cascade cyclization of Boc-protected benzylamines bearing two tethered alkyne moieties in a domino reaction initiated by a 6-endo-dig cyclization. The reaction was screened intensively, and the scope was explored, resulting in nine new Boc-protected dihydrobenzo[c]phenanthridines with yields of up to 98 %; even a π-extension and two bidirectional approaches were successful. Furthermore, thermal cleavage of the Boc group and subsequent oxidation gave substitut ...[more]

PMID: 34310792

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