Non-planar porphyrins with mixed substituent pattern: bromination and formylation of ethyl-substituted tetraphenylporphyrins and tetraalkylporphyrins

Bromination of porphyrins (Review)

“…Thus, the bromination of deuteroporphyrin with the perbromide of pyridinium bromide [68,100] and N-bromosuccinimide [101] An attempt at the bromination of 2,3-diethyltetraphenylporphyrin 68 with 2 equiv. of N-bromosuccinimide gave a complex mixture of reaction products, from which after repeated purification it was possible to obtain a small yield of the β-dibromo-substituted porphyrin 69a [51]. Exhaustive bromination at all the free β-positions of tetraphenylporphyrins with various number of ethyl groups [51] can be achieved by the method in [58].…”

“…of N-bromosuccinimide gave a complex mixture of reaction products, from which after repeated purification it was possible to obtain a small yield of the β-dibromo-substituted porphyrin 69a [51]. Exhaustive bromination at all the free β-positions of tetraphenylporphyrins with various number of ethyl groups [51] can be achieved by the method in [58].…”

C60Cl6, C60Br8 and C60(NO2)6 as Selective Tools in Organic Synthesis

“…TPP is often chlorinated with Nchlorosuccinimide yielding the polychlorinated as well as the monochlorinated product, with yields just under 50% (16). Callot reported monobromination at the b-position of the pyrrole ring (17), but Senge (18) later reported that he was unable to reproduce Callot's work; rather, polybromination at the b-positions of TPP and its derivatives occurred. For TPP the most common method of nitration is with Cu(NO 2 ) 2 N3H 2 O in acetic acid (16), but this reaction can be unpredictable if the porphyrin contains other acid-sensitive functional groups.…”

Synthesis and Reactivity of Allenylporphyrins

“…IR spectra were recorded on a Perkin-Elmer Spectrum 100 FT-IR spectrometer. Starting Materials: Formylporphyrins 1a, [29] 1b; [30] bromoporphyrins 4a, [31] 4j, [32] 4l; [31] dipyrromethane [15] , 5,15-disubstituted porphyrins: 8a, [33] 8b, [14b] 8c, [34] 8d, [14b] 8e, [35] 8f, [36] 10a, [37] 5,10,15-triphenylporphyrin 9a and the nickel(II) complex 11a, [39] and 5,15-bis(4-methylphenyl)-10-phenylporphyrin (9b) [40] were prepared using standard methodologies and had analytical data consistent with that in the literature. General Procedure A.…”