Dibenzothiophene-Containing Thiacarbaporphyrinoids.

A new type of expanded dibenzothiophene-containing thiacarbaporphyrinoid containing one dibenzothiophene, two -phenylene, one thiophene, and two pyrrole rings connected via four carbons and two direct bonds was synthesized over a sequence of six steps starting with commercially available dibenzothiophene. The X-ray structure obtained for one of the macrocycles revealed that the macrocycle was very nonplanar and the two -phenylene rings and dibenzothiophene unit were deviated from the mean plane, whereas the thiophene ring attained inverted conformation and was facing toward outside the macrocyclic core. The X-ray structure also revealed that the dibenzothiophene unit of the macrocycle maintained its π-electron delocalization and did not extend the π-electron delocalization with the rest of the macrocycle, and the effective π-conjugation was present only in the lower part of the macrocyclic core, i.

Synthesis and Studies of Di(p-Benzi)Decaphyrin and Di(9,10-Anthracenyl)Decaphyrin.

Two novel macrocycles, di(p-benzi)decaphyrin and di(9,10-anthracenyl)decaphyrin have been synthesized by condensing appropriate p-phenylene based pentapyrrane or 9,10-anthracenyl based pentapyrrane with pentafluorobenzaldehyde under acid catalyzed conditions. The pentapyrrane precursors were synthesized over sequence of steps starting with commercially available 1,4-dibromobenzene and 9,10-dibromoanthracene. The decaphyrin macrocycles were freely soluble in common organic solvents and characterized and studied by HR-MS, 1D and 2D NMR, absorption, cyclic voltammetry and computational techniques.

Synthesis and Properties of Nonaromatic Meta-Benziheptaphyrins and Aromatic Para-Benziheptaphyrins.

Two examples of nonaromatic m-benziheptaphyrins and two examples of aromatic p-benziheptaphyrins were synthesized by [5+2] condensation of appropriate m-benzi pentapyrrane and p-benzi pentapyrrane respectively and bithiophene diol in CH Cl in the presence of one equivalent of TFA under inert conditions for 30 min followed by oxidation with DDQ in open air for 1 h. The H NMR studies carried out at room temperature as well as at lower temperature indicated the nonaromatic nature of m-benziheptaphyrins with inversion of two thiophene rings and aromatic nature of p-benziheptaphyrins with inversion of one of the thiophene ring. The X-ray structure obtained for one of the p-benziheptaphyrins showed a planar conformation with alignment of one of the thiophene ring away from the macrocyclic inner core but maintained its coplanarity with the mean plane and supported the aromatic nature of the macrocycle.

Synthesis of Pyridine-Containing Crowned Fused Expanded Porphyrins.

New examples of nonaromatic fused expanded porphyrins containing both pyridine and crown ether moiety as a part of macrocyclic framework were synthesized by condensing pyridine based pentapyrrane with polyether-based diol in CH Cl in the presence of one equivalent of BF  ⋅ OEt under inert conditions followed by oxidation with DDQ in open air. The condensation was expected to form pyridine-containing crowned expanded porphyrins but resulted in the formation of fused crowned expanded porphyrins due to intramolecular fusion of two pyrrole nitrogens with two adjacent inverted thiophene carbons as revealed by X-ray crystallography obtained for one of the macrocycle. HRMS and NMR studies supported the formation of fused crowned pyridine containing expanded porphyrins, and the macrocycles showed simple, well-resolved NMR spectra where all resonances were identified easily by 2D NMR spectroscopy.

Synthesis and Structural Properties of NIR-Absorbing Pyridine-Containing Heptaphyrins.

Four examples of stable nonaromatic pyridine containing heteroheptaphyrins (pyrithiaheptaphyrins) 2-5 were synthesized in 8-13% yields by [5+2] condensation of newly synthesized pyridine-based pentapyrrane 8 and bithiophene diol 9 a-d. The X-ray crystallographic analysis of macrocycle 2 proved that the macrocycle assumes a highly planar structure with two inverted thiophene rings. The heteroheptaphyrins 2-5 are asymmetric and showed a greater number of resonances in H NMR spectra compared to our previously reported symmetric heterohexaphyrin (pyrithiahexaphyrin) 1 c.

Synthesis and Studies of Stable Nonaromatic Dithia Pyribenzihexaphyrins.

We report here one of the rare examples of expanded hexaphyrins named as dithia pyribenzihexaphyrin macrocycles containing six-membered rings such as pyridine and -phenylene along with five-membered heterocycles such as pyrrole and thiophene as a part of a macrocyclic frame. Trifluoroacetic acid catalyzed [3 + 3] condensation of equimolar mixture of [10,10'-(--butyl phenyl)hydroxymethyl]-1,3-(2-thienyl)pyridine diol (2,6-pyri diol) and 1,4-(phenyl(1-pyrrol-2-yl)methyl)benzene (-benzidipyrrane) in CHCl followed by oxidation with DDQ afforded stable nonaromatic dithia 2,6-pyri--benzihexapyrins and in 6-8% yields. The macrocycles were characterized by high-resolution mass spectroscopy and 1D and 2D NMR spectroscopy.