Synthesis and spectroscopic and electrochemical characterization of ionic and .sigma.-bonded aluminum(III) porphyrins. Crystal structure of methyl(2,3,7,8,12,13,17,18-octaethylporphinato)aluminum(III), (OEP)Al(CH3)

Diboryl and Diboranyl Porphyrin Complexes: Synthesis, Structural Motifs, and Redox Chemistry: Diborenyl Porphyrin or Diboranyl Isophlorin?

“…In addition, the four multiplets that correspond to the butyl resonances are observed, they are well-separated and shifted upfield (ranging from d = À0.56 for the CH 3 group to À5.70 ppm for the a-CH 2 group) by the diamagnetic porphyrin ring current effect. Similar shifts are observed for the butyl proton resonances in the diamagnetic Group 13 por- [15] Ga [16] and In [17] ), and are compelling evidence for the presence of n-butyl groups above and below the porphyrin plane. The structure and 1 H and 11 B NMR spectra of unsubstituted porphyrin complex 3 have also been calculated (GIAO B3LYP/ 6-31G(d)//B3LYP/6-311 + GA C H T U N G T R E N N U N G (2d,p)), and the upfield chemical shifts calculated for the butyl groups qualitatively match those observed for 3 a in the The presence of both the butyl substituents and the B À B single bond were confirmed by an X-ray crystal structure determined for a crystal of 3 a grown from dichloromethane.…”

Electrochemical and Spectroscopic Characterization of Aluminium(III)-para-methyl-meso-tetraphenylporphyrin Complexes Containing Substituted Salicylates as Axial Ligands

“…p-CH 3 TPP-Al-Cl undergoes two reversible reductions at 1/2 = −1.15 and −1.50 V in CH 2 Cl 2 and 0.1 M (TBA)PF 6 . The absolute potential difference between these two processes is 0.35 V, which suggests that both electron additions occur at the porphyrin -ring system to generate an anion radical and dianion [33,34]. A dissociation of the Cl-counter ion may occur after electroreduction of p-CH 3 TPP-Al-Cl.…”

“…Under CH 2 Cl 2 solution conditions, p-CH 3 TPP-Al-4-CSA complex undergoes two oxidations at −0.60 and 0.57 corresponding to Al + /Al 2+ and Al 2+ /Al 3+ . The occurrence of a chemical reaction following the first one-electron oxidation of all p-CH 3 TPP-Al-X complexes has been suggested on the basis of data available from the literature [34]. This reaction involves a cleavage of the -X group and leads to the formation of ([p-CH 3 TPP-Al] + , as shown in the following:…”

Fluxional behavior of Al(Et)(q′)2 (q′=2-methyl-8-quinolinolato) studied by temperature dependent 1H NMR spectroscopy

“…Since penta-coordinate monoalkyl-aluminum complexes (e.g., AlMe(porphinano) and an AlMe(N-O) 2 type complex) usually take a tetragonal pyramidalstructure with the alkyl group deviated from the square planar plane formed with other ligands such as two N-O ligands in the AlMe(N-O) 2 type complex [7,8], Al(Et)(q 0 ) 2 is also considered to have a similar structure, as depicted in Scheme 1. The Form A structure is similar to that of the reported AlMe(N-O) 2 type complex [8].…”