Activation of cobalt–phthalocyanine catalyst by polymer attachment

Polymer-Attached Catalysts

“…Under homogeneous conditions, however, such complexes readily produce inactive species, which may be direct dimers or J-I-dioxo dimers formed by interaction between two complex molecules. If the porphyrin or phthalocyanine ligands are bound to polymer supports, dimerization is inhibited with the result that the catalytic activities of the polymer-anchored catalysts are greater than for the homogeneous catalysts [49]. Site isolation attributable to the polymer matrix has been confirmed by studies of the electronic and ESR spectra for the phthalocyanine complex anchored to a poly(vinylamine) support [50].…”

Phthalocyanines Containing Macrocycles

“…33 The second type of phthalocyanine polymer is the network polymers; such polymers are ideally formed from bis(phthalonitri1e) monomers. 86 It is known that replacement of the peripheral hydogen atoms in phthalocyanine itself by bulky substituents increases the solubility dramatically. This polymerization was first studied using 3,3', 4,4'-tetracyanodiphenyl ether in a heterogeneous fusion reaction."…”

Diruthenium(I,I) Catalysts for the Formation of β‐ and γ‐Lactams via Carbenoid CH Insertion of α‐Diazoacetamides

“…They were compared with the timehonored catalyst Rh 2 A C H T U N G T R E N N U N G (OAc) 4 (4) which served as a benchmark and source of comparison with literature reports. Furthermore, a comparison of catalysts 7a-c with the dirhodium-bisA C H T U N G T R E N N U N G (calix [4]arenedicarboxylate) complex 6 [27] was made in order to learn whether the additional calixarene ligand would influence the chemoselectivity of the carbenoid reaction. Finally, we included also [RuCl 2 A C H T U N G T R E N N U N G (p-cymene)] 2 (11) in this investigation because of the recent report that this complex is highly active for the high-yielding transformation of 3-keto-2-diazocarboxamides into lactams.…”

“…Succinimidyl diazoacetate (1) was synthesized with slight modification as described previously. [17,36] Catalysts 5, [37] 6, [27] 7a-c, [23] 8, [24] and 9 [25] were prepared as described in the literature. The activity of catalyst 8 decreases on storing; therefore, it was re-activated prior to use by dissolution in dry acetonitrile, warming at 60 8C for 10 min and evaporation of the solvent in a flow of argon.…”