Meso-Substituted Corroles from Nitrosoalkenes and Dipyrromethanes

Abstract

The synthesis of bilanes and hexapyrroles containing an oxime functionality, prepared by two and three consecutive hetero-Diels−Alder reactions (or conjugated additions) between nitrosoalkenes and dipyrromethanes, is described. Bilanes underwent oxidative macrocyclization to afford a new class of trans-A 2 Bcorroles. Porphyrins could also be obtained by reacting bilanes with aldehydes in the presence of trifluoroacetic acid, followed by an oxidative step.

Corroles and Hexaphyrins: Synthesis and Application in Cancer Photodynamic Therapy

“…The above-described syntheses of corroles were based on classical methodologies involving acid-catalyzed condensation of pyrroles or meso -substituted dipyrromethanes and aldehydes, followed by oxidation. Recently, Pinho e Melo et al described an innovative synthesis of A 2 B-type corroles, bearing an oxime functionality, by exploring the reactivity of dipyrromethanes toward nitrosoalkenes ( Scheme 9 ) [ 43 ]. In situ dehydrohalogenation of the α,α-dihalo-oximes 23 generates transient α-chloro-nitrosoalkenes, which react with dipyrromethanes either via hetero-Diels−Alder reaction or conjugated addition to give the corresponding alkylated dipyrromethanes.…”

Direct Construction of Corrole‐Peptide Conjugates by Controllable Bilane Formation on Resin

“…Additionally, Melo et al. provided an alternative methodology by using α, α‐dihalo‐oximes, instead of aldehydes, to give meso‐ oxime corroles with comparable overall yields (up to 26 %, two‐step) [11] . Despite the difficulty in synthesis (e. g., low yield, tedious purification steps, lots of by‐products involved, optimal conditions vary with substances, etc.…”

The role of solvents and concentrations in the properties of oxime bearing A2B corroles

“…630 nm. 20 Aiming to strategically develop photosensitizers and heterocycles with unique photophysical properties, [26][27][28] we have investigated the photophysical properties of the in house developed oxime-corrole derivatives 29 and 5,10,15-(triphenyl)corrole, from here referred to as the model compound (Fig. 1).…”