Syntheses and Functionalizations of Porphyrin Macrocycles

Abstract

Porphyrin macrocycles have been the subject of intense study in the last century because they are widely distributed in nature, usually as metal complexes of either iron or magnesium. As such, they serve as the prosthetic groups in a wide variety of primary metabolites, such as hemoglobins, myoglobins, cytochromes, catalases, peroxidases, chlorophylls, and bacteriochlorophylls; these compounds have multiple applications in materials science, biology and medicine. This article describes current methodology for preparation of simple, symmetrical model porphyrins, as well as more complex protocols for preparation of unsymmetrically substituted porphyrin macrocycles similar to those found in nature. The basic chemical reactivity of porphyrins and metalloporphyrin is also described, including electrophilic and nucleophilic reactions, oxidations, reductions, and metal-mediated cross-coupling reactions. Using the synthetic approaches and reactivity profiles presented, eventually almost any substituted porphyrin system can be prepared for applications in a variety of areas, including in catalysis, electron transport, model biological systems and therapeutics.

Efficient access to β-vinylporphyrin derivatives via palladium cross coupling of β-bromoporphyrins with N-tosylhydrazones

“…We believe that the mechanism of the formation of the β-alkenylporphyrin derivatives 3a–c follows the one reported by Barluenga [13,39–42]. …”

“…Porphyrin-type heterocycles are well known for their special role in several scientific fields, including medicine [1–3] , supramolecular chemistry [4–6] and catalysis [7–10]; their functionalization became a target for several research groups [11–13]. In particular, the insertion of functional groups into the macrocyclic core merits considerable attention due to the diversity of structural features that can be induced in the porphyrin structure [14–16].…”

Enhanced Cellular Uptake and Photodynamic Effect with Amphiphilic Fluorinated Porphyrins: The Role of Sulfoester Groups and the Nature of Reactive Oxygen Species

“…A major challenge in PDT is to develop PS molecules that absorb light in the phototherapeutic window-the 630-850 nm range-where human tissues are the most transparent. Porphyrin derivatives [5], including chlorins [6][7][8] and bacteriochlorins [6], as well as phthalocyanines [9][10][11], are the most frequently studied PDT photosensitizers due to their long-wavelength absorption and their photophysical properties (high yields of long-lived triplet states) [12][13][14][15]. The lowest-electronically excited triplet state of photosensitizer is the precursor of ROS-generating reactions.…”

Synthesis and Acid-base Properties of Isomeric Tetrachlorooctabromo- and Tetrabromooctachlorotetraphenylporphyrins

“…Synthetic porphyrins having a planar or almost planar molecules structure have been thoroughly studied. [1][2][3][4][5] However, according to the data, [6][7][8][9][10][11][12][13] the porphyrin macrocycle is flexible enough and can exist in no planar conformations. The ability of spatially distorted polyhalogensubstituted metalloporphyrins to exhibit catalytic activity in oxidation reactions is of great interest.…”