Cabort, Amel

2003, Cabort, Amel, Michel, Armelle, Therrien, Bruno, Stoeckli-Evans, Helen, Bernauer, Klaus, Süss-Fink, Georg, Williams, Alan F., Stupka, Gilles

The coordination of 2,6-bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine (L) to Ni, Ru, Fe, and Co was studied. The reaction with Ni salts gives the Ni(II) complex [Ni(L)2]2+ (1). The reaction of RuCl3 gives only the Ru(II) complex [Ru(L)2]2+ (2). In the case of Fe, both [Fe(L)2]2+ (3) and [Fe(L)2]3+ (4) were synthesized and characterized. In the case of Co, the Co(III) complex [Co(L)2]3+ (5) was obtained, even if a Co(II) salt was used. However, [Co(L)2]2+ (6) can be obtained under N. Mol. structures of 1-5 complexes were detd. by x-ray anal. of the corresponding perchlorate salts; the structure of 3 was solved for both the perchlorate and the tetrachloroferrate(III) salts. All complexes show an octahedral coordination geometry with meridional arrangement of the two tridentate ligands. The electrochem. behavior of 2, 3 and 6 was studied by cyclic voltammetry. Quasi reversible electron transfer is obsd. for the redox pairs FeIII/FeII and CoII/CoI. The reaction shows somewhat weaker reversibility for CoIII/CoII, whereas the reaction of RuIII/RuII is not reversible. The measurements suggest 2,6-bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine (L) to have a higher stabilization of low-valent oxidn. states of Fe and Co than terpyridine. [on SciFinder(R)]

2002, Cabort, Amel, Therrien, Bruno, Stoeckli-Evans, Helen, Bernauer, Klaus, Süss-Fink, Georg

In Scheme 1, the N atom was missing at several places; the cor. scheme is given. [on SciFinder(R)]

2003, Cabort, Amel, Therrien, Bruno, Bernauer, Klaus, Süss-Fink, Georg

Copper(II) azido complexes contg. a tridentate trinitrogen ligand, [Cu(?3-L)(N3)]+ [L = 2,6-bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine] as well as [Cu(?3-R,S-LH4)(N3)]+, [Cu(?3-S,S-LH4)(N3)]+ and [Cu(?3-R,R-LH4)(N3)]+ [LH4 = 2,6-bis(pyrrolidin-2-yl)pyridine] were synthesized from Cu(ClO4)2·6H2O, NaN3 and the corresponding tridentate ligand and crystd. from methanol as the perchlorate salts. The single crystal x-ray structure analyses show these complexes to form 1-dimensional networks by Cu···N(azide) intermol. interactions, depending on the conformation of the tridentate ligand. In the case of L, an excess of sodium azide gives [Cu(?3-L)(N3)]2[Cu2Cl2(N3)4], the crystal structure anal. of which reveals a surprising tridimensional network of cationic and anionic copper(II) complexes linked by Cu···N(azide) and Cu···N(L) interactions. [on SciFinder(R)]

2002, Cabort, Amel, Therrien, Bruno, Bernauer, Klaus, Süss-Fink, Georg

Crystals of the title compd. are monoclinic, space group C2/c, with a 11.434(2), b 10.630(2), c 20.948(4) Å, ? 100.12(3)°; Z = 4, dc = 1.534; R = 0.026, Rw(F2) = 0.059 for 2341 reflections. The structure of the mononuclear octahedral Rh(III) complex possesses a 2-fold axis passing through Rh, the equatorial Cl atom and the N atom pyridine ring. [on SciFinder(R)]

2002, Cabort, Amel, Therrien, Bruno, Stoeckli-Evans, Helen, Bernauer, Klaus, Süss-Fink, Georg

Reaction of 2,6-bis(pyrrolidin-2-yl)pyridine (LH4) with RuCl3·3H2O in refluxing MeOH/H2O mixts. gives the octahedral complexes [Ru(LH4)(L)]2+, in which one of the two trihapto ligands was dehydrogenated as 2,6-bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine (L), even if LH4 was present in excess. With the three stereoisomers of LH4, [Ru(R,S-LH4)(L)]2+ (meso), [Ru(R,R-LH4)(L)]2+ and [Ru(S,S-LH4)(L)]2+ were isolated as the perchlorate salts and characterized by x-ray structure anal. and by CD spectra. [on SciFinder(R)]

2002, Cabort, Amel, Therrien, Bruno, Bernauer, Klaus, Süss-Fink, Georg

The tetrafluoroborate salt of the mononuclear octahedral Ru(II) complex, [RuCl(L)(PPh3)2]BF4, where L = 2,6-bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine, was prepd. as the CH2Cl2 solvate. Crystals are triclinic, space group P?1, with a 10.3368(8), b 12.7939(11), c 19.1336(16) Å, ? 80.231(10), ? 89.193(9), ? 67.943(9)°; Z = 2, dc = 1.505; R = 0.031, Rw(F2) = 0.076 for 8322 reflections. The PPh3 ligands adopt a trans configuration, with a P-Ru-P angle of 173.72(2)°. [on SciFinder(R)]