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which consists of two pyrene units fixed intramolecularly in an ecliptic face-to-face orientation with parallel pyrene axes has been synthesized: 2,7-bis(bromomethyl)-pyrene (2) and 2,7-bis(mercaptomethyl)pyrene (3), the preparations of which are described, were cyclised to 2,15-dithia[3.3](2,7)pyrenophane (10). The disulfone 11 derived from 10 yielded 1 by vacuum vapour phase pyrolysis (5OO0C/0.1 torr). -For an analogous synthesis of the isomeric [2.2](1,6)pyrenophane (12), which might exist as two stereoisomers with parallel and crossed pyrene axes, 1,6-bis(bromomethyl)pyrene (13) and 1,6-bis(mercaptomethyl)pyrene (14) were prepared. Cyclisation of 13 and 14, so far, yielded the corresponding dithia[3.3](1,6)pyrenophane only in traces. -Absorption, fluorescence and phosphorescence spectra (Figure 1) of 1 as well as the zero field splitting parameter ID lof the excited triplet state (determined by ODMR) are discussed with regard to transannular interactions and on the basis of the X-ray structure analysis of 1 (Figure 2).Forster und Kasper') haben vor 25 Jahren beobachtet, da13 bei Losungen des Pyrens mit zunehmender Konzentration statt der normalen Pyren-Fluoreszenz eine neue breite und strukturlose Emissionsbande auftritt, die um rund 6000 cm-' langwellig verschoben ist. Da das Absorptionsspektrum unverandert bleibt, wurde diese Emission einem im Grundzustand nicht stabilen angeregten Dimer (AA)* zugeschrieben, das durch As-*) Korrespondenz bitte an diesen Autor richten. **) Herrn Professor Georg Wittig in dankbarer Erinnerung an viele Jahre gemeinsamen Wirkens an der Universitat Heidelberg zum 16. Juni 1979 gewidmet.

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Durch Alkylierung des Cyclopentanopyridins (II) mit den β‐Lactam‐Derivaten (I) erhält man das Antibioticum (III).

The eDlission spectra of [2.21 (2,7)pyrenophane and the zero field splitting parameters D und E of its excited triplet elate were measured in glasses and in amaU siogle cry .. ~.Ls at 1.3 .K. The .results are beiDg compand with monomer pyrene and 2.7·dimelbylpyrene in liqUid and solid solultons as weD as in lingle C1')'I1815.