Synthesis 2002(6): 0749-0752
DOI: 10.1055/s-2002-25769
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Atropisomeric 1,8-Bis(4′,4′-dipyridyl)naphthalenes from 4-Trimethylstannylpyridines

Christian Wolf*, Bereket T. Ghebremariam
Department of Chemistry, Georgetown University, Washington, DC 20057, USA
Fax: +1(202)6876209; e-Mail: cw27@georgetown.edu;
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Publikationsverlauf

Received 11 December 2001
Publikationsdatum:
26. April 2002 (online)

Abstract

Two synthetic strategies towards atropisomeric 2′,2′-di­substituted 1,8-bis(4′,4′-dipyridyl)naphthalenes using Stille cross-coupling of trimethylstannylpyridine derivatives and 1,8-di­iodonaphthalene have been investigated. Introduction of substituents into the pyridyl moieties prior to the cross-coupling step provides higher overall yields than derivatization of 1,8-bis(4′,4′-dipyridyl)naphthalene under Ziegler reaction conditions.

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Isolated by flash chromatography (EtOAc-hexanes-Et3N, 200:200:1). The yield is based on 7. 1H NMR: δ = 7.47-7.58 (m, 8 H), 8.00 (d, J = 1.5 Hz, 2 H), 8.07 (dd, J = 1.5, 5.1 Hz, 4 H), 8.84 (d, J = 5.1 Hz, 2 H). EI-MS (70 eV): m/z (%) = 308 (100, M+), 280 (12, M+ - CH2N), 231 (11, M+ - Ph), 204 (24, M+ - Ph, - HCN), 176 (13, M+ - Ph, - HCN, - CH2N), 154 (31, M+ - 2Ph).