1234628-35-3Relevant articles and documents
Synthetic, structural, and photophysical exploration of meso-pyrimidinylsubstituted AB2-corroles
Ngo, Thien H.,Puntoriero, Fausto,Nastasi, Francesco,Robeyns, Koen,Van Meervelt, Luc,Campagna, Sebastiano,Dehaen, Wim,Maes, Wouter
experimental part, p. 5691 - 5705 (2010/08/20)
meso-Pyrimidinyl-substituted AB2-corroles were efficiently synthesized starting from 5-mesityldipyrromethane and various 2-substituted 4,6-dichloropyrimidine-5-carbaldehydes. The corroie yield was significantly enhanced by optimization of the amount of Lewis acid catalyst (BF3-OEt2). The main advantage of pyrimidinylcorroles over other meso-triarylcorroles is their wide range of functionalization possibilities, which has been explored by nucleophilic and electrophilic aromatic substitution, and Pd-catalyzed crosscoupling reactions. Stepwise substitution of the chlorine functions afforded asymmetrically substituted pyrimidinylcorroles. Due to the lability of the freebase corroie macrocycles, functionaliza tion of the corroie periphery was preferentially performed on the Cu-metalated counterparts. Functionalized freebase AB2-pyrimidinylcorroles were, however, readily accessible by the reversible sequence Cu insertion and subsequent reductive demetalation. AB2-pyrimidinylcorroles can hence be regarded as highly versatile platforms towards more sophisticated corrole systems. X-ray analysis of a bis(4-tert-butylphenoxy)-substituted Cu-pyrimidinylcorrole showed the typical features of a Cu-corrole: short N-Cu distances and a saddled corroie plane. The absorption spectra and photophysical properties of some representative freebase AB2-pyrimidinylcorroles were examined in depth. The absorption spectra displayed typical corroie features: intense spin-allowed π-π* bands, which can be classified as Soret- and Q-type bands. The photophysical properties, investigated both in fluid solution at room temperature and in rigid matrix at 77 K, were governed by the lowestlying π-π* singlet state; however, in most cases, a state with partial chargetransfer character (from the corroie ring to the pyrimidinyl group) was proposed to contribute to the dynamic properties of the emissive level.
