Synthesis of 2,2′-bipyrrole-5-carboxaldehydes and their application in the synthesis of B-ring functionalized prodiginines and tambjamines
作者:Papireddy Kancharla、Kevin A. Reynolds
DOI:10.1016/j.tet.2013.07.067
日期:2013.9
Facile, versatile, and cost-effective synthetic routes for the preparation of a range of new 3-alkyl-, 4-alkyl-, 3,4-dialkyl-, and 3-halo-4-alkyl-2,2′-bipyrrole-5-carboxaldehydes have been developed. These 2,2′-bipyrrole-5-carboxaldehydes offer interesting potential as building blocks for making bioactive natural and unnatural products, as demonstrated by the synthesis of B-ring functionalized prodiginines
Regiocontrolled Synthesis of Pyrrole-2-carboxaldehydes and 3-Pyrrolin-2-ones from Pyrrole Weinreb Amides
作者:Aaron R. Coffin、Michael A. Roussell、Elina Tserlin、Erin T. Pelkey
DOI:10.1021/jo061043m
日期:2006.8.1
A regiocontrolledsynthesis of 3,4-disubstituted pyrrole-2-carboxaldehydes was completed in two steps from acyclic starting materials. A Barton−Zard pyrrolesynthesis between N-methoxy-N-methyl-2-isocyanoacetamide and α-nitroalkenes or β-nitroacetates provided N-methoxy-N-methyl pyrrole-2-carboxamides (pyrrole Weinreb amides), which were converted into the corresponding pyrrole-2-carboxaldehydes by
Syntheses of per-15N labeled etioporphyrins I–IV and a related tetrahydrobenzoporphyrin for applications in organic geochemistry and vibrational spectroscopy
作者:Timothy D. Lash、Shaohua Chen
DOI:10.1016/j.tet.2005.09.105
日期:2005.12
and assignment of vibrational spectra for sedimentary porphyrins. Etioporphyrin-I was prepared via pyrromethene intermediates, while etioporphyrins II–V and a related tetrahydrobenzoporphyrin were synthesized via stepwise routes involving the copper(II) mediated cyclization of a,c-biladienes as the key step. Detailed analyses of both the proton and carbon-13NMRspectra provide nitrogen-15 coupling
作者:Timothy D. Lash、John R. Bellettini、Jolie A. Bastian、Kendall B. Couch
DOI:10.1055/s-1994-25431
日期:——
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 nitroalkenes,in refluxing tetrahydrofuran. These pyrrolic products are important intermediates in the synthesis of porphyrins and related compounds.
Dimethyl acetylenedicarboxylate, ethyl propiolate, nitro olefins, or 2-nitroalkyl acetates react with thioimidate in the presence of organic bases to give the corresponding pyrroles in moderate-to-good yields.