Details

Autor(en) / Beteiligte

• Vale, Matthew
• Pink, Maren
• Rajca, Suchada
• Rajca, Andrzej

Titel

Synthesis, Structure, and Conformation of Aza[1 n ]metacyclophanes

Ist Teil von

• Journal of organic chemistry, 2008-01, Vol.73 (1), p.27-35

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

2008

Quelle

MEDLINE

Beschreibungen/Notizen

• N-Benzyl substituted aza[1 n ]metacyclophanes (n = 4, 6, 8, and 10) were prepared in overall 40% isolated yields via Pd-catalyzed aminations. Analyses of the reaction mixtures showed that aza[14]metacyclophane and the related polymer were the primary products (∼60% overall yield); aza[1 n ]metacyclophanes up to n = 14 and linear oligomers with up to 20 nitrogen atoms (with at least three types of end groups) were detected. Macrocyclic structures for n = 4, 6, and 10 were confirmed by X-ray crystallography. 1,3-Alternate (D 2 d ) and 1,3,5-alternate (S 6) conformations in solution on NMR time scale at low temperatures were found for macrocycles with n = 4 and n = 6, respectively; the barrier for ring inversion was considerably lower for the larger macrocycle.