51089-83-9Relevant articles and documents
Artificial photosynthetic reaction centers with carotenoid antennas
Gould, Stephanie L.,Kodis, Gerdenis,Liddell, Paul A.,Palacios, Rodrigo E.,Brune, Alicia,Gust, Devens,Moore, Thomas A.,Moore, Ana L.
, p. 2074 - 2096 (2007/10/03)
Two reaction center-antenna models based on a purpurin macrocycle linked to a C60 and to a carotenoid polyene have been synthesized. In these systems the C60 moiety is the primary electron acceptor, the purpurin is the primary electr
Porphyrins with exocyclic rings. Part 12. Synthesis of meso,β-butano- and meso,β-pentanoporphyrins from cycloalka[b]pyrroles
Bastian, Jolie A.,Lash, Timothy D.
, p. 6299 - 6310 (2007/10/03)
Pyrroles 5 with b-face fused seven- or eight-membered carbocyclic rings were prepared in good yields by Knorr-type condensations with cycloheptanone or cyclooctanone, respectively. Treatment with lead tetraacetate in dichloromethane afforded the labile ω-acetates 8 and subsequent acid catalyzed condensation with α-unsubstituted pyrrole-2-carboxylates yielded the related pyrrolylcycloalka[b]pyrroles 29 and 30. The α-unsubstituted pyrroles 14 and 23 were prepared by condensing α,β-unsubstituted ketones, or their β-acetoxycarbonyl precursors, with benzyl N-tosylglycinate in the presence of DBU, followed by dehydration with POCl3-pyridine and base catalyzed elimination of p-toluenesulfinic acid. Dipyrrole dibenzyl esters 29 and 30 were hydrogenolysed over 10% Pd-C to give the corresponding dicarboxylic acids. Acid catalyzed condensation with diformyldipyrrylmethane 33 under modified MacDonald '2 + 2' conditions afforded a series of four cycloalkanoporphyrins 4a-d with seven- or eight-membered exocyclic rings. Although the meso,β-butanoporphyrins 4a and 4b were isolated in good yields, poorer results were obtained for the related meso,β-pentanoporphyrin: 4c and 4d. It is proposed that the eight-membered carbocyclic ring distorts the geometry of the open-chain tetrapyrrolic intermediates and this deleterious influence results in the lower yields observed.
Synthesis of pyrroles from benzyl isocyanoacetate
Lash,Bellettini,Bastian,Couch
, p. 170 - 172 (2007/10/02)
Benzyl esters of 5-unsubstituted pyrrole-2-carboxylic acids were prepared in excellent yields by the base-catalyzed condensation of benzyl isocyanoacetate with α-acetoxynitro compounds, or nitro-alkenes, in refluxing tetrahydrofuran. These pyrrolic products are important intermediates in the synthesis of porphyrins and related compounds.
