Novel loop-like aromatic compounds: a further step on the road to nanobelts and nanotubes

• Venkataramana Rajuri,
• Dariush Ajami,
• Gaston R. Schaller,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2010, 6, No. 30, doi:10.3762/bjoc.6.30

• characterization of new compounds 2–6 were accomplished. As a common synthetic methodology, the Diels–Alder reaction was applied to 9,9′,10,10′-tetradehydrodianthracene (TDDA) (7) to furnish the [12]annulenes 2 and 3 [16]annulene 6 and adduct 5. Keywords: [n]annulenes; Diels–Alder reaction; nanobelts

• ; tetradehydrodianthracene; Introduction The first loop-like (in plane) conjugated molecules [1][2] prepared by rational synthesis were reported 13 years ago [3][4][5]. Unlike “normal” cyclic conjugated rings with p orbitals perpendicular to the ring plane such as benzene, the p orbitals of belt-like conjugated structures

• reaction [7][8][11] and ring enlargement metathesis [12][13][14][15] of 9,9′,10,10′-tetradehydrodianthracene (TDDA) (7) [16]. In a second step we anticipated closing the tube walls by cyclodehydrogenation [17]. Results and Discussion We now report on the synthesis of five new compounds, two hydrocarbons