Crystal structure of 5,10,15,20-tetrakis(5′-methylthien-2′-yl)porphyrin, C40H30N4S4

Abstract

C40H30N4S4, triclinic, P1̅ (no. 2), a = 6.5126(7) Å, b = 10.499(1) Å, c = 12.635(1) Å, α = 87.818(2)°, β = 79.141(2)°, γ = 86.737(2)°, V = 846.7 Å3, Z = 1, Rgt(F) = 0.057, wRref(F2) = 0.150, T = 100 K.

Origin of the bathochromically shifted optical spectra of meso-tetrathien-2′- and 3′-ylporphyrins as compared to meso-tetraphenylporphyrin

“…In all the solid state structures of meso-thienyl group containing porphyrins, such as free base meso-tetrakis-2-thienylporphyrin (2b), 34 the Zn(II) 35 and Cu(II) 36 complexes of 2a and in examples of meso-tetrathien-2 0 -and 3 0 -yldithiaporphyrins, 14 the thienyl groups adopt the typical, near-perpendicular position. The average dihedral angle of 621 between the thienyl and porphyrin mean plains observed for 2b is also within the 60-801 angle typically observed in meso-tetraarylporphyrins (Fig.…”

“…5A). 34 Evidently, the thienyl groups are not small enough to assume in the crystal a low-energy co-planar conformation with the porphyrin ring. Though the o-carbon-b-carbon distances are slightly longer than those observed in the crystal structure of 1 (Table 3), suggesting a larger conformational freedom, the C ortho -C ipso -C meso -C a dihedral angles are comparable.…”

Synthesis, EPR and DFT calculations of rare Ag(II)porphyrins and the crystal structure of [Zn(II)tetrakis(4-bromo-2-thiophene)porphyrin]

“…The packing seems to be controlled by C-HÁÁÁp interactions with HÁÁÁp distance of 2.773(2) Å between the thiophene rings and the porphyrin pyrrolic rings, and notably SÁÁÁS interactions at a distance of 3.420(4) Å (see Figure S1). The latter distinguishes 4 from the three other available thiophene-porphyrin structures, and indeed, the freebase tetrakis-5-methyl-thiophene porphyrin [16] and the [Cu(II)(tetrakis-(2-thiophene-porphyrin)] [17] have both co-planar porphyrin rings while [Zn(II)(tetrakis-(2-thiophene-porphyrin)] [15] have the porphyrins inclined with a 67.4°angle.…”

“…Furthermore, oligomeric [10,11] and polymeric [12] meso-tetrakis-thiophene porphyrin films have shown promising properties as robust catalysts for the oxidation of organic substrates [13,14]. Despite this, and the importance of intermolecular interactions in many applications, there are only three reported Xray structures of thiophene-substituted porphyrins [15][16][17].…”

“…Furthermore, oligomeric [10,11] and polymeric [12] meso-tetrakis-thiophene porphyrin films have shown promising properties as robust catalysts for the oxidation of organic substrates [13,14]. Despite this, and the importance of intermolecular interactions in many applications, there are only three reported Xray structures of thiophene-substituted porphyrins [15][16][17].Moreover, in coordination chemistry, one intriguing possibility is the stabilization of the very unusual Ag(II) oxidation state, [18] although these examples are rare indeed compared to other metalloporphyrins [19][20][21][22][23][24][25][26][27][28]. It should be noted that this is not just a curiosity, it is important to have well-characterized examples of such unusual oxidation states in order to identify them also in other, perhaps more transient and unstable species.…”