Multi‐Cation Coordination in Porphyrinoids

Abstract

Porphyrinoidm acrocyclesa re unbreakablyl inked with the coordination of central cations that drastically influence the observed behavior.Aspecific place has been recorded for structures where more than one cation is entrapped in as ingle macrocycle.I th as been ac haracteristic feature of expanded porphyrinoids where the increased coordination space allows am ultiple coordination. Because of spe-cific steric confinements, an incorporation of more than one cation within regular or contracted porphyrinoids is more demanding but it can be realizedo ns everal ways significantly modifying the observed behavior.W ew ill discusss ynthetic strategies leadingtos tructures with increased number of cations and the influence on the observedb ehavior of such modification.

Two Rhodium(III) Ions Confined in a [18]Porphyrin Frame: 5,10,15,20‐Tetraaryl‐21,23‐Dirhodaporphyrin

“…protons of rhodacyclopentadiene subunits on the basis of their splitting by 103 Rh nucleus, with relatively small 3 J RhH coupling constants, ranging from 0.7 Hz (2-H) to 2.3 Hz (3), characteristic for this nuclide. In case of 13 C NMR spectra, RhÀ 13 C�O signals show large 1 J RhC coupling constants (71-75 Hz), similar to literature values for terminal carbonyls (70 Hz), [34] allowing their easy discrimination from α-rhodacycle carbon-13 signals, appearing in the same spectral range, but featuring much smaller 1 J RhC coupling constants (26-30 Hz), similar to 1 J RhCsp2 detected in rhodium(III) benziporphyrin complexes (23-26 Hz). [35]…”

“…[11] Porphyrinpincer hybrids evolved in subsequent studies into double-and triple-cavity hybrid macrocycles, like "earring porphyrins" (V, Scheme 1). [12,13] An entirely different type of a multi-metal porphyrin derivative can be formed on the basis of σ metalmetal bonds extending over a metalloporphyrin ring, [14] exemplified by a tin(II)porphyrin with attached Mn(CO) 4 À HgÀ Mn(CO) 5 unit (VI, Scheme 1). [15] Insertion of two central ions into a porphyrin cavity is possible in case of boron, the only element small enough to fit in the standard [18]porphyrin core.…”

Bispalladium(II) Complexes of di‐p‐Pyrirubyrin Derivatives as Promising Near‐Infrared Photoacoustic Dyes

“…The expanded porphyrins, macrocyclic systems with typically improved conjugation and an increased delocalization pathway, have been extensively explored for their optical, electrochemical, and coordination properties [2, 3] . In addition, due to a larger macrocyclic cavity, they have generated complexes containing more than one metal ion, efficiently increasing the conjugation [4–6] …”

Kinetic trapping of a cobalt(ii) metallocage using a carbazole-containing expanded carbaporphyrinoid ligand

“…[23][24][25][26][27][28][29] These unique macrocycles exhibit a diverse range of properties, including unusual aromaticity and chirality features, [30][31][32] as well as serving as potential ligands. [33][34][35][36] Among the various expanded carbaporphyrinoids reported to date, those with two embedded polyaromatic hydrocarbons or related heterocycles (PAHs) are still relatively rare and their metalation chemistry has not been extensively explored. 37,38 Recently, we reported the synthesis of the meso-free expanded carbaporphyrinoid 3.…”