A Mixed‐Valence Bis‐Phosphorus Complex Entrapped in a Oxatriphyrin(3.1.1) Surrounding

Abstract

The macrocyclic, porphyrinic environment has been reported as a ligand capable of accommodating different types and numbers of cations. The number of coordinated cations strongly depends on the coordination sphere size, which usually limits the possibility of forming multicationic structures to higher oligomers of macrocycles. Even for structures with enlarged coordination spheres, two interacting phosphorus ions with different oxidation states entrapped in a single organic frame are rarely reported. Oxatriphyrin(3.1.1) adapts its properties to form a mixed‐valence, bis‐phosphorus complex with a P–O–P unit entrapped. The macrocycle adjusts its coordination properties actively by involving the meso carbon atom to bind two phosphorus atoms with different oxidation states. The final complex presents emission properties that are characteristic for a triheterocyclic, fully conjugated fragment but that are tunable by the second PV ion.

Synthesis of [14]Oxatriphyrins(2.1.1) and Their Transformation into Ethane‐Bridged Oxatripyrrins by Boron Complexation

“…The HOMO and LUMO energy levels of 6 and 7 are slightly higher and lower than those of the boron complex of bOTP (bOTP-B), respectively, which means that the HOMOs and LUMOs make similar contributions to the frameworks of the oxatriphyrins. [24,[53][54][55][56] Both boron complexes 8 and 9 in dichloromethane show strong fluorescence at 595 (Φ f = 38 %, τ f = 6.0 ns) and 590 nm (Φ f = 58 %, τ f = 7.1 ns), respectively. The absorption spectra of 8 and 9 show peaks at 556 and 554 nm, respectively, without the porphyrin-like absorption features.…”

“…[23][24][25][26][27] To date, three synthetic methods have been established for preparing the triphyrin framework: 1) The modified Lindsey method, [8,14] 2) the intramolecular McMurry coupling method, [9] and 3) the [2+1] condensation method. [23][24][25][26][27] To date, three synthetic methods have been established for preparing the triphyrin framework: 1) The modified Lindsey method, [8,14] 2) the intramolecular McMurry coupling method, [9] and 3) the [2+1] condensation method.…”

Three‐Stage Aromaticity Switching in Boron(III) and Phosphorus(V) N‐Fused p‐Benziporphyrin

“…Such N‐fusion rearrangements have been subsequently reported for expanded (hetero)porphyrins as shown for phosphorus(V) complexes of a triply‐fused [24]pentaphyrin 3‐P . In general the listed examples ( 1 – 3 ) encompassed a triphyrin( n .1.1)‐like environment, exemplified by archetypal oxatriphyrin(3.1.1) 4 (Scheme ), appropriately matching the cationic radii of central ions . Thus the introduction of fused rings into the macrocyclic core can be treated as an important way to generate new classes of ligands that can adapt to specific ions and form B/P‐X (X=N, O, C) bonds and thus influencing the properties of such molecules.…”

Shaping a Porphyrinoid Frame by Heteroatoms Extrusion: Formation of an Expanded [22]Triphyrin(6.6.0)

“…Triphyrins (Scheme 1) constitute ar elatively new porphyrinoid family, [1,2] including macrocycles dispersed in size from the smallest classical triphyrins(1.1.1) [3,4] in their basic tripyrrolic form known only as boron(III) complexes, through versatile ligands,t riphyrins(2.1.1), [5][6][7][8][9][10] then modestly represented triphyrins(3.1.1) [11][12][13][14] to triphyrins(4.1.1), [15][16][17][18][19] and finally to av ery flexible macrocycle,t riphyrin(6.1.1). [20][21][22][23][24] The above triphyrin(n.1.1) series does not include the very first heterotriphyrins(2.2.2) reported by Badgere tal., [25,26] named [ 18]annulene sulfides/ oxides.…”

“…The bowl-shapeda romatic boron(III) [14]triphyrins(1.1.1), commonlyn amed boron(III) subporphyrins, can be synthesized using several, typically boron-templated, protocols, by cyclization of pyrrolic units in the presence of ab oron(III) template, [4,[27][28][29] or by tripyrrane boron-assisted cyclization. [30] The formed boron complexes do not undergo an extrusion of the boron ion, making impossible the exploration of the coordination chemistry of subporphyrins.…”