crystallzed from EtOAc, m.p. >300"C, m/z (EIMS) 502; 'H-NMR (CDCI,): 6 = 1.81 (m. 4H). 2.33 (m, 4H), 2.61 (m, 4H), 4.92 (s, 4H), 4.97 (bs, 4H), 4.99 ( s , 4H). 5.09 ( s , 4H), 6.99 (s, 2H); "C-NMR (CDCI?): 6=25.7, 43.2, 85.0, 85.3, 100.9, 110.2, 143.1, 144.2, 144.61. 6a: 6 (156 mg, 0.88 mmol) was heated under reflux (48 h, N2) with anthracene (50 mg, 0.28 mmol) in xylene (5 mL): yield of the crude product: after chromatography (SiO,/CHCI,-Et,O) 17 mg, I Io/i. Colorless crystals [m.p. >300"C), m/z (positive ion FABMS) 535 for (M+H)O] suitable for X-ray crystallography, were grown by the vapor diffusion method (CHCI,. CICHzCH,Cl-light petroleum). Reaction (CH2Cl2,10 kbar, 55-60"C. 200 h) of 7 (373 mg, 0.74 mmol) with 5 (156 mg, 0.74 mmol) yielded, after chromatography (SiO2/CHCl3-MeOH), 8 [I05 mg, 20%, recrystallized from CHCI?, m.p. > 300"C, m/z (positive ion FABMS) 713 for (M+H)@: 'H-NMR (CDCI,): 6=1.62 (m, 4H), 2.32(m,8H),2.63(m,8H),4.89(~,8H),5.08(~,4H),6.98(~,4H): "C-NMR (CDC13): 6=27.1, 44.2, 84.8, 86.6, I10.1, 144.6, 152.51, which was also obtained in very low yield (3.5%) by heating 6 under reflux (48 h, N2) in xylene. Single crystals, suitable for X-ray analysis, were obtained by slow evaporation of a chloroform solution of 8 at room temperature. German version: Angew. Chem. 99 (1987) 941 Champions of highly speculative projects are few and far between; here, they were Dr. R . D. Handscombe (University of Sheffield) and Prof. G. Stagno dXlcontres (University of Messina). We thank them for their moral support-and for their enthusiastic efforts, a// the many postgraduate students, who over the years, have received their introduction to the research laboratory in Sheffield making starting materials for "the crazy molecule". One of the authors (J. F. S.) also thanks the Leverhulme Trust for the award of a Research Fellowship. :Recently, some force-field calculations have been carried out (R. W.Alder, R. B. Sessions, J. Chem. Sac. Perkin Trans. 2 1985, 1849) on molecular belts built from cyclohexa-1,4-diene rings. Compounds of the type 1 were referred to in the above paper as [nlbeltenes; the strain energy per 2-butene-l,2,3,4-tetrayI unit was found to decrease monotonically from [3]beltene to [12]beltene. Calculations on encapsulated complexes of small molecules led to the prediction that, in the case of acetylene, for example, [9]beltene will be the optimum molecular receptor.

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A collection of smart multicomponent reactions (MCRs) with continuative post condensation cyclizations (PCCs) is presented to construct conventional three- to seven-membered heterocyclic compounds in diversity oriented syntheses (DOS). These will provide a high degree of applying economical and ecological advantages as well as of practicability. Water, ionic liquids, and solvent-less syntheses as well as use of various forms of energy as microwave and ultrasonic irradiation are examined and discussed.

Thermisch stabil, wenig flüchtig, einfach zu transportieren und zu lagern, exakt dosierbar – das sind die Vorteile von Kohlensäure‐bis(trichlormethylester) 1 als Phosgen‐Ersatz. Darüber hinaus genügen stöchiometrische Mengen 1 für Chlorformylierungen, Carbonylierungen, Chlorierungen und Dehydratisierungen, die obendrein mit guten bis sehr guten Ausbeuten verlaufen.magnified image

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Several novel methods, catalysts and reagents have been developed to improve organic synthesis. Synergistic effects between reactions, reagents and catalysts can lead to minor heats of reaction and occur as an inherent result of multicomponent reactions (MCRs) and their extensions. They enable syntheses to be performed at a low energy level and the number of synthesis steps to be drastically reduced in comparison with ‘classical’ two-component reactions, fulfilling the rules of Green Chemistry. The very high potential for variability, diversity and complexity of MCRs additionally generates an extremely diverse range of products, thus bringing us closer to the aim of being able to produce tailor-made and extremely low-cost materials, drugs and compound libraries.

Phosgene is quantitatively formed from solid triphosgene in a solvent-free and safe process without any reaction heat, catalyzed by planar N-heterocycles with deactivated imino functions. The rate of phosgene generation is adjustable to the rate of phosgene consumption in the subsequent phosgenation reaction by thermal control, catalyst concentration, and in some cases, specific properties of selected metal phthalocyanines. A thermal runaway reaction of this process is impossible.