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While materials based on organic molecules usually have either superior optoelectronic or superior chiral properties, the combination of both is scarce. Here, a crystalline chiroptical film based on porphyrin with homochiral side groups is presented. While the dissolved molecule has a planar, thus, achiral porphyrin core, upon assembly in a metal–organic framework (MOF) film, the porphyrin core is twisted and chiral. The close packing and the crystalline order of the porphyrin cores in the MOF film also results in excellent optoelectronic properties. By exciting the Soret band of porphyrin, efficient photoconduction with a high On‐Off‐ratio is realized. More important, handedness‐dependent circularly‐polarized‐light photoconduction with a dissymmetry factor g of 4.3×10−4 is obtained. We foresee the combination of such assembly‐induced chirality with the rich porphyrin chemistry will enable a plethora of organic materials with exceptional chiral and optoelectronic properties. [ABSTRACT FROM AUTHOR]

Herein, a series of four amide-bonded hydroxyquinoline-substituted porphyrins have been prepared and characterized. Trends in the electronic structures are investigated by spectroscopic and electrochemical analysis to explore the effect of the functional amide-bonded hydroxyquinoline units. Also, the selective pH sensing properties were also performed and their plausible mechanism were also proposed. And the proposed mechanisms is the photoinduced electron transfer mechanism. [ABSTRACT FROM AUTHOR]

The Co(II) complex of a new D2-symmetric chiral porphyrin 3,5-DiMes-QingPhyrin, [Co(P6)], can catalyze asymmetric aziridination of alkenes with bis(2,2,2-trichloroethyl)phosphoryl azide (TcepN3) as a nitrene source. This new Co(II)-based metalloradical aziridination is suitable for different aromatic olefins, producing the corresponding N-phosphorylaziridines in good to excellent yields (up to 99%) with moderate to high enantioselectivities (up to 85% ee). In addition to mild reaction conditions and generation of N2 as the only byproduct, this new metalloradical catalytic system is highlighted with a practical protocol that operates under neutral and non-oxidative conditions.

Inside Back Cover: Twisting of Porphyrin by Assembly in a Metal-Organic Framework yielding Chiral Photoconducting Films for Circularly-Polarized-Light Detection (Angew. BINOL, Chiral Porphyrin, Circularly Polarized Light, Metal-Organic Frameworks, Photodetectors While the porphyrin molecules in solution (red) are planar, as common porphyrin, the porphyrin cores are twisted and chiral upon assembly in the metal-organic framework. [Extracted from the article]

We have synthesized three complexes of 5-(8-ethoxycarbonyl-l-naphthyl)-10,15,20-triphenyl porphyrin (ENTPP), [Cu(ENTPP)], [Ni(ENTPP), and [Fe(ENTPP)Cl], X-ray crystallography reveals that copper and nickel species are four-coordinate, while the iron complex is five-coordinate. The porphyrin in all the three species maintains similar conformations, in which rotational hindrance makes the ester group at the 8-position of naphthyl lie above the porphyrin plane leading to axial chirality in the single molecule. However, only chiral crystals of [Cu(ENTPP)] were obtained by spontaneous resolution upon crystallization, while [Ni(ENTPP) and [Fe(ENTPP)CI] were obtained as achiral crystals of racemic compounds. CD spectra have also confirmed the chirality of the crystalline samples. The origin of CD signals has also been discussed. [ABSTRACT FROM AUTHOR]

Abstract: Infrared spectral study of bistable chiral porphyrins. Chiral porphyrins in which adjacent meso substituents are connected by a strap via ester linkages and their metal complexes have been examined by infrared spectroscopy. These compounds can adopt several conformations depending on the length of the strap as well as on the nature of the complexing metal. The multiplicity of the carbonyl stretching vibration is correlated to the symmetry of these complexes, and therefore it provides information on their conformation. This observation is potentially useful in the case of paramagnetic complexes where NMR spectroscopy is uninformative. To cite this article: A. Castaings et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: Peripherally palladated Ni(II) porphyrins have been prepared using enantiopure chiral chelating diphosphines as supporting ligands on the attached Pd(II) fragment. Both enantiomers of the following complexes have been obtained in good yields, using oxidative addition of the bromoporphyrin starting material 5-bromo-10,20-diphenylporphyrinatonickel(II) (NiDPPBr (1)) to the [Pd0L] complex generated in situ from Pd2dba3 and the chiral ligand L: [PdBr(NiDPP)(CHIRAPHOS)] (2a,b) [CHIRAPHOS=2,3-bis(diphenylphosphino)butane], [PdBr(NiDPP)(Tol-BINAP)] (3a,b) [Tol-BINAP)=2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl] and [PdBr(NiDPP)(diphos)] [diphos=1,2-bis(methylphenylphosphino)benzene] (4a,b). The induced asymmetry in the porphyrin was readily detected by 1H NMR and CD spectroscopy. The porphyrin chiroptical properties are strongly dependent upon the structure of the chiral ligand, such that a monosignate CD signal, and symmetric and asymmetric exciton couplets were observed for 4a, 2b, and 3a,b, respectively. [Copyright &y& Elsevier]

Herein, a series of three methyl red-porphyrin hybrids containing one, two and three amide-bonded chiral chromophores were successfully synthesized and isolated. Interestingly, these methyl red-porphyrin chiral hybrids have significant expansion in both UV–vis absorption and circular dichroism spectra. Furthermore, the expanded chiral-optical responses can be modulated under UV-light irradiation due to the trans - and cis -isomerism of –N N- bond of methyl red chromophore. • A series of three chiral methyl red-porphyrin hybrids were synthesized and isolated. • These methyl red-porphyrin chiral hybrids have significant expansion in both UV–vis and CD spectra. • The expanded chiral-optical responses can be modulated under UV-light irradiation. [ABSTRACT FROM AUTHOR]

The Co(II) complex of a new D 2-symmetric chiral porphyrin 3,5-DiMes-QingPhyrin, [Co(P6)], can catalyze asymmetric aziridination of alkenes with bis(2,2,2-trichloroethyl)phosphoryl azide (TcepN3) as a nitrene source. This new Co(II)-based metalloradical aziridination is suitable for different aromatic olefins, producing the corresponding N-phosphorylaziridines in good to excellent yields (up to 99%) with moderate to high enantioselectivities (up to 85% ee). In addition to mild reaction conditions and generation of N2 as the only byproduct, this new metalloradical catalytic system is highlighted with a practical protocol that operates under neutral and non-oxidative conditions.