15072-08-9

Upstream product

• 1003-29-8 2-pyrrole aldehyde 
• 95-54-5 1,2-diamino-benzene 
• 108-45-2 m-phenylenediamine 

Downstream Products

• 742059-41-2 [Ru(bis(pyrrole-2-carboxaldehyde)-1,2-phenylenediimine)Cl₂(PPh₃)(H₂O)] 

Relevant academic research and scientific papers

Molecular recognition: Preorganization of a bis(pyrrole) schiff base derivative for tight dimerization by hydrogen bonding

Multiple techniques have been used to delineate the self-assembly of a bis(pyrrole) Schiff base derivative (compound 4, C16H 14N4), which forms an unusual dimer through complementary N-H...N=C hydrogen bonds between twisted, C2-symmetric monomer units. The asymmetric unit of the crystal structure comprises one and a half dimer units, with one dimer exhibiting approximate D2 point-group symmetry and the other exact D2 symmetry (space group C2/c). The dimers pack into columns whose axes are collinear with the a axis of the unit cell. The columns assemble into discrete layers with two distinct types of hydrogen-sized voids residing between the layers. Despite the promising architec ture of the voids within the lattice of 4, the absence of genuine channels to interconnect the voids precludes the uptake of hydrogen gas, even at elevated pressures (10 bar). AM1 calculations of the structure of dimeric 4 indicate that self-recognition through hydrogen bonding depends primarily on favorable electrostatic interactions. The potential-energy surface for monomeric 4 mapped by counter-rotation of an adjacent pair of C=C-N=C torsion angles indicates that the X-ray structures of the four monomeric units are global minima with highly nonplanar conformations that are preorganized for self-recognition by hydrogen bonding. The in vacuo enthalpy of association for the dimer was calculated to be significantly exergonic (ΔGassoc = -21.9 kJ mol-1, 298 K) and in excellent agreement with that determined by 1H NMR spectroscopy in CDCl3 (AGassoc = -16.6(4) kJ mol -1, 298 K). Using population and bond order analyses, in conjunction with the conformation dependence of the frontier MO energies, we have been able to show that π-electron delocalization is only marginally diminished in the nonplanar conformers of 4 and that the electronic structures of the constituent monomers of the dimer are well mixed.

Heterogeneous green catalyst for oxidation of cyclohexene and cyclooctene with hydrogen peroxide in the presence of host (nanocavity of Y-zeolite)/guest (N4-Cu(II) Schiff base complex) nanocomposite material

Copper(II) complex of a Schiff base ligand derived from pyrrolcarbaldehyde and o-phenylenediamine (H2L) has been synthesized and encapsulated in Y-zeolite matrix. The hybrid material has been characterized by elemental analysis, IR and UV-Vis s

Luminescent di- and trinuclear boron complexes based on aromatic iminopyrrolyl spacer ligands: Synthesis, characterization, and application in OLEDs

New bis- and tris(iminopyrrole)-functionalized linear (1,2-(HNC4H3-C(H)-N)2-C6H4 (2), 1,3-(HNC4H3-C(H)-N)2-C6H4 (3), 1,4-(HNC4H3-C(H)-N)2-C6H4 (4), 4,4′-(HNC4H3-C(H)-N)2-(C6H4-C6H4) (5), 1,5-(HNC4H3C-(H)-N)2-C10H6 (6), 2,6-(HNC4H3C-(H)-N)2-C10H6 (7), 2,6-(HNC4H3C-(H)-N)2-C14H8 (8)) and star-shaped (1,3,5-(HNC4H3-C(H)-N-1,4-C6H4)3-C6H3 (9)) π-conjugated molecules were synthesized by the condensation reactions of 2-formylpyrrole (1) with several aromatic di- and triamines. The corresponding linear diboron chelate complexes (Ph2B[1,3-bis(iminopyrrolyl)-phenyl]BPh2 (10), Ph2B[1,4-bis(iminopyrrolyl)-phenyl]BPh2 (11), Ph2B[4,4′-bis(iminopyrrolyl)-biphenyl]BPh2 (12), Ph2B[1,5-bis(iminopyrrolyl)-naphthyl]BPh2 (13), Ph2B[2,6-bis(iminopyrrolyl)-naphthyl]BPh2 (14), Ph2B[2,6-bis(iminopyrrolyl)-anthracenyl]BPh2 (15)) and the star-shaped triboron complex ([4′,4′′,4′′′-tris(iminopyrrolyl)-1,3,5-triphenylbenzene](BPh2)3 (16)) were obtained in moderate to good yields, by the treatment of 3-9 with B(C6H5)3. The ligand precursors are non-emissive, whereas most of their boron complexes are highly fluorescent; their emission color depends on the π-conjugation length. The photophysical properties of the luminescent polyboron compounds were measured, showing good solution fluorescence quantum yields ranging from 0.15 to 0.69. DFT and time-dependent DFT calculations confirmed that molecules 10 and 16 are blue emitters, because only one of the iminopyrrolyl groups becomes planar in the singlet excited state, whereas the second (and third) keeps the same geometry. Compound 13, in which planarity is not achieved in any of the groups, is poorly emissive. In the other examples (11, 12, 14, and 15), the LUMO is stabilized, narrowing the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO), and the two iminopyrrolyl groups become planar, extending the size of the π-system, to afford green to yellow emissions. Organic light-emitting diodes (OLEDs) were fabricated by using the new polyboron complexes and their luminance was found to be in the order of 2400 cd m-2, for single layer devices, increasing to 4400 cd m-2 when a hole-transporting layer is used. Bridge the gap: Luminescent linear and star-shaped polynuclear organoboron complexes containing iminopyrrolyl ligands linked by aryl bridges were synthesized, showing good luminescent properties depending on π-conjugation lengths of the molecules (see figure). Organic light-emitting diodes (OLEDs) were successfully fabricated with the new boron complexes, achieving luminance values of up to 4400 cd m-2.

Bis(pyrrolidene) Schiff Base Aluminum Complexes as Isoselective-Biased Initiators for the Controlled Ring-Opening Polymerization of rac-Lactide: Experimental and Theoretical Studies

A series of bis(pyrrolidene) Schiff base aluminum complexes (1-7) were synthesized and characterized by NMR spectroscopy and elemental analysis. All complexes were efficient initiators for the ring-opening polymerizations of l-LA and rac-LA in toluene at

Synthesis, properties, and reactivity of a series of non-heme {FeNO} 7/8 complexes: Implications for Fe-nitroxyl coordination

The biochemical properties of nitroxyl (HNO/NO-) are distinct from nitric oxide (NO). Metal centers, particularly Fe, appear as suitable sites of HNO activity, both for generation and targeting. Furthermore, reduced Fe-NO-/Fe-HNO or

Distinct nanostructures from isomeric molecules of bis(iminopyrrole) benzenes: Effects of molecular structures on nanostructural morphologies

The effects of molecular structures on nanostructural morphologies have been studied through the preparation of nanospheres, square nanowires, and nanocubes from three isomeric molecules of bis(iminopyrrole)benzene. The Royal Society of Chemistry.

Complementary hydrogen bonding in a new tridentate Schiff base ligand: X-ray, DFT and solution NMR studies

The X-ray crystal structure of a novel mono(pyrrole)-containing tridentate Schiff base ligand, N-[(1E)-1H-pyrrol-2-ylmethylene]benzene-1,2-diamine (3), shows unexpected hydrogen bond complementarity between neighbouring pairs of molecules in the solid state (monoclinic space group C2). The supramolecular structure is best described as a hinged dimer in which the dihedral angle between the two ligand planes measures 65(1)° and is stabilized by a pair of hydrogen bonds involving the pyrrole N-H proton on one molecule and the N atom of the aryl amino group on the neighbouring molecule. The experimental H(pyrrole)...N(amine) H-bond distances are equivalent at 2.40(2) A. The 1H NMR spectrum of 3 in CDCl 3 shows concentration-dependent features that are consistent with endergonic dimerization by intermolecular hydrogen bonding at higher concentrations [KD = 0.89(16) M-1 at 25°C]. DFT calculations at the B3LYP/6-31G** level of theory correctly predict the main geometrical features of the dimer, which has slightly inequivalent H(pyrrole)...N(amine) distances of 2.31 and 2.33 A in the calculated structure. The DFT-calculated dimer shows some conformational differences from the X-ray structure that primarily reflect the fact that the individual molecules of 3 in the in vacuo model are twisted about the C=N-C=C torsion angle involving the imine group and adjacent phenyl ring (C5-N2-C6-C7) by 4-8° more than is the case for the experimental structure. These conformational differences reflect the role that crystal packing plays in fine-tuning the supramolecular structure of 3.

Reduction of dioxygen by a dimanganese unit bonded inside a cavity provided by a pyrrole-based dinucleating ligand

A novel class of dinucleating ligands has been introduced into manganese chemistry to study the reactivity of this metal towards dioxygen under strictly controlled conditions. Such N4 ligands combine some of the major peculiarities of tetradent

Synthesis and characterization of some pyrrole-based aldimine monomers

Several new pyrrole-based aldimine monomers were synthesized by catalyzed-condensation of an appropriate aromatic or aliphatic diamine with pyrrole 2-carboxaldehyde (1:2 molar ratio). Their structure was proved by infrared and NMR spectroscopy and element