Synthesis of an organic-soluble π-conjugated [3]rotaxane via rotation of glucopyranose units in permethylated β-cyclodextrin

• Jun Terao,
• Yohei Konoshima,
• Akitoshi Matono,
• Hiroshi Masai,
• Tetsuaki Fujihara and
• Yasushi Tsuji

Beilstein J. Org. Chem. 2014, 10, 2800–2808, doi:10.3762/bjoc.10.297

• ]rotaxane by a cross-coupling or complexation reaction of thus formed pseudo linked [3]rotaxane. Oligo(para-phenylene), oligothiophene, and porphyrin derivatives were used as π-conjugated guests with stopper groups. Keywords: cross-coupling reaction; insulated π-conjugated molecule; oligothiophene

• -phenylene) [23] and oligothiophene [24] with linked [3]rotaxane structures via the flipping phenomenon [25]. Results and Discussion Kano and co-workers reported the synthesis of a linked pseudo [3]rotaxane involving a water-soluble porphyrin unit with carboxylate groups as the guest unit by double self

• -inclusion via sequential flipping of permethylated β-cyclodextrin (PM β-CD) in water [26]. To synthesize an organic-soluble insulated π-conjugated rotaxane, we applied this technique to the synthesis of an insulated porphyrin without water-soluble functional groups. The synthetic route to the PM β-CD based

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• cancerous rather than squamous tissues [1]. δ-Aminolevulinic acid (1, ALA, Scheme 1) is a δ-amino acid precursor in the cellular biosynthesis of heme [2]. The penultimate step in this biosynthetic cycle is the iron chelation of protoporphyrin IX (PpIX), a porphyrin photosensitizer (PS) which was shown to be

Copolymerization and terpolymerization of carbon dioxide/propylene oxide/phthalic anhydride using a (salen)Co(III) complex tethering four quaternary ammonium salts

• Jong Yeob Jeon,
• Seong Chan Eo,
• Jobi Kodiyan Varghese and
• Bun Yeoul Lee

Beilstein J. Org. Chem. 2014, 10, 1787–1795, doi:10.3762/bjoc.10.187

• /diglycolic anhydride using a diiminate zinc catalyst has been reported. Here, the block copolymer of poly(ester-block-carbonate) was formed through the faster reaction of CHO/anhydride coupling, and after complete conversion of the anhydride, the carbonate block was grown by CO2/CHO coupling [29]. Porphyrin

Synthesis of the first examples of iminosugar clusters based on cyclopeptoid cores

• Mathieu L. Lepage,
• Alessandra Meli,
• Anne Bodlenner,
• Céline Tarnus,
• Francesco De Riccardis,
• Irene Izzo and
• Philippe Compain

Beilstein J. Org. Chem. 2014, 10, 1406–1412, doi:10.3762/bjoc.10.144

• ], β-cyclodextrin [4][5] and porphyrin [7] cores, and with nanoparticles prepared by self-assembly of iminosugar-based glycopolypetides [6]. So far, the largest multivalent effect (up to 610-fold relative inhibition potency increase on a valency-corrected basis) has been achieved on jack bean α

• ). These results may indicate that the ligand spatial presentation in cyclopeptoid-based iminosugars 10 is not optimal to achieve a substantial multivalent effect. It has been shown recently that the use of rigid scaffolds such as porphyrin or C60 could lead to large multivalent effects (up to 200-fold on

Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• demonstrated how cyclo-p-phenylenes of suitable size are able to form very stable complexes with C60 [20]. Aida and co-workers have reported on π-electron rich, porphyrin-based cyclic structures, which are able to selectively recognize C60 [21]. In subsequent work, similar porphyrin-based systems have been

Synthesis of chiral N-phosphoryl aziridines through enantioselective aziridination of alkenes with phosphoryl azide via Co(II)-based metalloradical catalysis

• Jingran Tao,
• Li-Mei Jin and
• X. Peter Zhang

Beilstein J. Org. Chem. 2014, 10, 1282–1289, doi:10.3762/bjoc.10.129

• Jingran Tao Li-Mei Jin X. Peter Zhang Department of Chemistry, University of South Florida, Tampa, Florida 33620, USA 10.3762/bjoc.10.129 Abstract 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

• 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. Keywords: asymmetric aziridination; aziridine; chiral porphyrin

• a racemic olefin aziridination system with diphenylphosphoryl azide (DPPA) using Co(II) complexes of common porphyrin ligands as catalysts, including [Co(TPP)] (Scheme 1) [20]. Despite the first demonstration of DPPA as a new nitrene source, this Co(II)-based catalytic transformation, however

First synthesis of meso-substituted pyrrolo[1,2-a]quinoxalinoporphyrins

• Dileep Kumar Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2014, 10, 808–813, doi:10.3762/bjoc.10.76

• -triphenylporphyrin. The reaction of this porphyrin with 2,5-dimethoxytetrahydrofuran, followed by the reduction of the nitro group in the presence of NiCl2/NaBH4 afforded 5-(3-amino-4-(pyrrol-1-yl)phenyl)-10,15,20-triphenylporphyrin. This triphenylporphyrin underwent a Pictet–Spengler cyclization after the reaction

• with various aromatic aldehydes followed by in situ KMnO4 oxidation to form target porphyrin analogues in good yields. The structures of all synthesized products were established on the basis of spectral data and elemental analyses. Keywords: Clauson–Kaas reaction; fluorescence; pyrrolo[1,2-a

• useful as fluorescent materials for various applications [36][37]. In recent years, numerous covalent or non-covalent supra-porphyrin arrays, based on donor–acceptor architectures have been constructed for mimicking the natural photosynthetic light harvesting systems [38][39][40]. Additionally, a variety

From porphyrin benzylphosphoramidate conjugates to the catalytic hydrogenation of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin

• Marcos C. de Souza,
• Leandro F. Pedrosa,
• Géssica S. Cazagrande,
• Vitor F. Ferreira,
• Maria G. P. M. S. Neves and
• José A. S. Cavaleiro

Beilstein J. Org. Chem. 2014, 10, 628–633, doi:10.3762/bjoc.10.54

• , Portugal 10.3762/bjoc.10.54 Abstract Three new porphyrin aminoalkyl dibenzylphosphoramidates were synthesized by nucleophilic aromatic substitution of one p-fluorine atom of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin (TPPF20) by primary aminoalkyl dibenzylphosphoramidates. The nucleophilic aromatic

• hydrogenation; chlorin; isobacteriochlorin; phosphoramidate; porphyrin; Introduction The use of porphyrin derivatives as photosensitizers is considered for the photodynamic therapy (PDT) of malignant tumors and the treatment of age-related macular degeneration in several countries [1][2]. It is already known

• that the efficiency of the drug greatly depends on the porphyrin amphiphilicity, which must provide good interactions with the lipid membranes and the physiological medium. Consequently, tumor localization and better selectivity can be achieved by introducing polar substituents [3]. For this reason, we

Tuning the interactions between electron spins in fullerene-based triad systems

• Maria A. Lebedeva,
• Thomas W. Chamberlain,
• E. Stephen Davies,
• Bradley E. Thomas,
• Martin Schröder and
• Andrei N. Khlobystov

Beilstein J. Org. Chem. 2014, 10, 332–343, doi:10.3762/bjoc.10.31

• magnetic properties of the resulting materials. This is essential for the recording, storing and read-out processes performed in spin-based quantum information processing using nanoscale molecular architectures [3]. This has been achieved recently within a copper porphyrin–N@C60 dyad [4] and several types

Synthesis of meso-substituted dihydro-1,3-oxazinoporphyrins

• Satyasheel Sharma and
• Mahendra Nath

Beilstein J. Org. Chem. 2013, 9, 496–502, doi:10.3762/bjoc.9.53

• Satyasheel Sharma Mahendra Nath Department of Chemistry, University of Delhi, Delhi 110 007, India 10.3762/bjoc.9.53 Abstract Novel dihydro-1,3-oxazinoporphyrins and naphtho[e]bis(dihydro-1,3-oxazinoporphyrin) derivatives, in which the porphyrin macrocycle is covalently linked to the dihydro-1,3

• type reaction; synthesis; Introduction Porphyrin macrocycles are of crucial interest for their potential applications in diverse fields such as biomimetic models for photosynthesis [1][2], electronic materials [3], catalysis [4] and medicine [5][6]. In the past few decades, the synthesis of porphyrin

• [25], pyrrolidinone [26], pyrrolidine [27] and piperazine [28], to the porphyrin periphery. In addition, many porphyrin dimers and trimers have displayed significant biological efficacy [29] and some of these are used as photosensitizers in PDT applications for the treatment of various types of

Control over molecular motion using the cis–trans photoisomerization of the azo group

• Estíbaliz Merino and
• María Ribagorda

Beilstein J. Org. Chem. 2012, 8, 1071–1090, doi:10.3762/bjoc.8.119

• two terminal units of porphyrin–Zn noncovalently associated to a host molecule of bis-isoquinoline 13 (Figure 14). The exposure of azo derivative 13 to light of λ = 350 ± 10 nm leads to a mixture of isomers trans/cis 22:78. Irradiation of this mixture of isomers at λ > 420 nm returns the system to an

• that distances the porphyrin units, causing a mechanical spin rotation in the bis-isoquinoline molecule similar to a pedal. This device is effective if the porphyrin–Zn and bis-isoquinoline units remain associated during the photoisomerization, i.e., the dynamics of dissociation between these units is

Synthesis of multivalent host and guest molecules for the construction of multithreaded diamide pseudorotaxanes

• Nora L. Löw,
• Egor V. Dzyuba,
• Boris Brusilowskij,
• Lena Kaufmann,
• Elisa Franzmann,
• Wolfgang Maison,
• Emily Brandt,
• Daniel Aicher,
• Arno Wiehe and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2012, 8, 234–245, doi:10.3762/bjoc.8.24

• attempts to use the same conditions for the fourfold coupling of 1 to 15 to synthesize tetravalent wheel 16 were unsuccessful, and we finally used another procedure for the cross-coupling reaction [107]. Because the Cu(I) catalyst may interfere with the Zn core of porphyrin 15 or lead to Glaser coupled

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• incorporate porphyrin linkers between two oxacalix[3]arenes, but, due to the size of the porphyrins and their rigidity, only the capsular form was found [50]. Treatment with zinc(II) acetate introduced three equivalents of the metal, one for each porphyrin unit. 3.2.3 Capping the upper rim: Capping the upper

• [53]. Capsule 46 was shown to bind to C60 by the presence of two peaks in the 13C NMR spectrum, which did not coalesce even at 90 °C. 1H NMR was used to determine an association constant of 54 M−1 in Cl2CDCDCl2 at 60 °C. An asymmetric capsule incorporating an oxacalix[3]arene and three Zn(II)porphyrin

Synthesis and crystal structures of multifunctional tosylates as basis for star-shaped poly(2-ethyl-2-oxazoline)s

• Richard Hoogenboom,
• Martin W. M. Fijten,
• Guido Kickelbick and
• Ulrich S. Schubert

Beilstein J. Org. Chem. 2010, 6, 773–783, doi:10.3762/bjoc.6.96

• reported. The use of tetra- and hexa-tosylates, based on (di)pentaerythritol as initiators for the CROP of 2-ethyl-2-oxazoline, resulted in very slow initiation and ill-defined polymers, which is most likely caused by steric hindrance in these initiators. As a consequence, a porphyrin-cored tetra-tosylate

• halide initiators, such as tetrakis(bromomethyl)ethylene, yielding 4-armed star-shaped polymers [10], as well as other multi-halide initiators based on, e.g., cyclotriphosphazine [11], silesquioxane [12], porphyrin [13][14] and bipyridine metal complex [15][16] cores. More recently, Jordan and coworkers

• . To circumvent the poor initiation efficiency with the multi-tosylate pentaerythritol derivatives, a tetra-tosylated porphyrin (TetraTos-B) was designed in which the rigid porphyrin keeps the tosylate groups far apart. Scheme 2 depicts the schematic path that was followed to synthesize TetraTos-B, and

Synthesis, electronic properties and self-assembly on Au{111} of thiolated (oligo)phenothiazines

• Adam W. Franz,
• Svetlana Stoycheva,
• Michael Himmelhaus and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2010, 6, No. 72, doi:10.3762/bjoc.6.72

• [18], porphyrin derivatives [20], phenanthrenes [22][23], fullerenes [24], and optically active naphthalenes [25] adsorbed on gold were studied in break-junction experiments and their properties on conductance, 1-bit random access memory and, especially, with regard to their ability to function as

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

Versatile supramolecular reactivity of zinc-tetra(4-pyridyl)porphyrin in crystalline solids: Polymeric grids with zinc dichloride and hydrogen-bonded networks with mellitic acid

• Sophia Lipstman and
• Israel Goldberg

Beilstein J. Org. Chem. 2009, 5, No. 77, doi:10.3762/bjoc.5.77

• Sophia Lipstman Israel Goldberg School of Chemistry, Sackler Faculty of Exact Sciences, Tel Aviv University, 69978 Ramat Aviv, Tel Aviv, Israel 10.3762/bjoc.5.77 Abstract Crystal engineering studies confirm that the zinc-tetra(4-pyridyl)porphyrin building block reveals versatile supramolecular

• connectivity between the component species. Keywords: coordination polymers; crystal engineering; hydrogen-bonded networks; porphyrin assemblies; supramolecular chemistry; Introduction The tetra(4-pyridyl)porphyrin entity in its free-base (TPyP) as well as its metallated (MTPyP) forms has an extraordinarily

• rich supramolecular chemistry, playing an important role in the construction of diverse polymeric architectures. The TPyPs are readily available [1], and the tendency of the zinc-porphyrin derivative to form polymeric chains by self-coordination between the peripheral pyridyl sites of one molecule and