Vertauscht man eine β‐Methineinheit und das N‐Atom eines Pyrrolrings, erhält man den neuen Porphyrinisomertyp 1, der durch Kondensation von Pyrrol und p‐Tolylaldehyd entsteht. Als vierzähniger Ligand, d. h. über die drei N‐Atome und das C‐Atom des inneren Cyclus koordiniert 1 überraschenderweise NiII‐Ionen. Das Gerüst des grünen Metalloporphyrins ist planar.magnified image
Octulene,t he higher homologue of kekulene and septulene,was synthesized using the fold-in method. This new hydrocarbon macrocycle contains al arge 24-membered inner circuit, which is peripherally fused to 24 benzenerings.Such an arrangement produces considerable hyperbolic distortion of the p-conjugated surface.T he consequences of distortion in octulene were explored using photophysical methods,w hich revealed ar educed electronic band gap and greater flexibility of the p system. Octulene contains af unctional cavity with ad iameter larger than 5.5 that is capable of efficiently binding the chloride anion in an onpolar solvent (K a = 2.2(4) 10 4 m À1 ,1 %d ichloromethane (DCM) in benzene). The octulene-chloride interaction is stabilized by eight weak C(sp 2 )H···Cl bonds,p roviding the first example of ah ydrocarbon-based anion receptor.
ABSTRACT. We seek to examine the manner in which either the EU member states of France, the Netherlands, Poland, and Sweden or parts of them, such as the country of England in the UK or the Flemish Region in Belgium, deal with the distributional effects of the flood risk management strategies prevention, defense, and mitigation. Measures carried out in each of these strategies can cause preflood harm, as in the devaluation of property or loss of income. However, different member states and authorities address this harm in different ways. A descriptive overview of the different compensation regimes in the field of flood risk management is followed by an analysis of these differences and an explanation of what may cause them, such as the geographical differences that lead to differences in the way that they interfere with private rights and the dominant legal principles that underlie compensation regimes. An elaborated compensation regime could lead to more equitable and legitimate flood risk management because the burdens are fairly spread and all interests-including those of injured parties-are considered in the decision-making process. Our aim is to stimulate the hardly existent discussion on the financial harm that is caused by measures to prevent floods (preflood), in addition to the already existing discussion on the ex post flood distributional effects.
Chiral heteroaromatic propellers based on radially p-extended hexapyrrolohexaazacoronenes were obtained in ac oncise synthesis from suitably functionalizedd onoracceptor monopyrroles.T oo vercome steric hindrance,anew cyclodehydrogenation method was developed, and it uses bromine electrophiles as oxidative coupling agents instead of the commonly employed high-potential oxidants.T he new reaction offers high yields of propeller-shaped targets,even for electron-deficient precursors,a nd shows electrophile-dependent stereoselectivity,w ith N-bromosuccinimide and dibromine yielding,r espectively D 6 -a nd C 2 -symmetric products. The propeller azacoronenes are chiral and can be separated into configurationally stable enantiomers.I na ddition to providing steric bulk, peripheral functionalization considerably affects the electronic properties of the propellers,w hich exhibit reduced optical and electrochemical band gaps,a nd amore clearly defined electroreduction behavior.
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