@misc{lindsey_muthukumaran_ptaszek_huma_s._2008, title={Boron complexation strategy for use in manipulating 1-acyldipyrromethanes}, volume={7,317,108}, number={2008 Jan. 8}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Lindsey, J. S. and Muthukumaran, K. and Ptaszek, M. and Huma, H. Z. and S.}, year={2008} }
 @misc{lindsey_muthukumaran_ptaszek_h._2007, title={Boron complexation strategy for use in manipulating 1-acyldipyrromethanes}, volume={7,282,582}, number={2007 Oct. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Lindsey, J. S. and Muthukumaran, K. and Ptaszek, M. and H., Zaidi. S.}, year={2007} }
 @article{dogutan_zaidi_thamyongkit_lindsey_2007, title={New route to ABCD-porphyrins via bilanes}, volume={72}, ISSN={["1520-6904"]}, DOI={10.1021/jo701294d}, abstractNote={A new strategy for preparing porphyrins that bear up to four different meso-substituents (ABCD-porphyrins) relies on two key reactions. One key reaction entails a directed synthesis of a 1-protected 19-acylbilane by acid-catalyzed condensation at high concentration (0.5 M) of a 1-acyldipyrromethane and a 9-protected dipyrromethane-1-carbinol (derived from a 9-protected 1-acyldipyrromethane). Three protecting groups (X) were examined, including thiocyanato, ethylthio, and bromo, of which bromo proved most effective. The bilanes were obtained in 72-80% yield, fully characterized, and examined by 15N NMR spectroscopy. The second key reaction entails a one-flask transformation of the 1-protected 19-acylbilane under basic, metal-templating conditions to give the corresponding metalloporphyrin. The reaction parameters investigated for cyclization of the bilane include solvent, metal salt, base, concentration, temperature, atmosphere, and time. The best conditions entailed the 1-bromo-19-acylbilane at 100 mM in toluene containing DBU (10 mol equiv) and MgBr2 (3 mol equiv) at 115 degrees C exposed to air for 2 h, which afforded the magnesium porphyrin in 65% yield. The magnesium porphyrin is readily demetalated to give the free base porphyrin. A stepwise procedure (which entailed treatment of the 1-(ethylthio)-19-acylbilane to oxidation, metal complexation, desulfurization, carbonyl reduction, and acid-catalyzed condensation) was developed but was much less efficient than the one-flask process. The new route to ABCD-porphyrins retains the desirable features of the existing "2 + 2" (dipyrromethane + dipyrromethane-1,9-dicarbinol) method, such as absence of scrambling, yet has significant advantages. The advantages include the absence of acid in the porphyrin-forming step, the use of a metal template for cyclization, the ability to carry out the reaction at high concentration, the lack of a quinone oxidant, avoidance of use of dichloromethane, and the increased yield of macrocycle formation to give the target ABCD-metalloporphyrin.}, number={20}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Dogutan, Dilek Kiper and Zaidi, Syeda Huma H. and Thamyongkit, Patchanita and Lindsey, Jonathan S.}, year={2007}, month={Sep}, pages={7701–7714} }
 @misc{lindsey_muthukumaran_ptaszek_zaidi_2006, title={Boron complexation strategy for use in manipulating 1-acyldipyrromethanes}, volume={7,153,975}, number={2006 Dec. 26}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Lindsey, J. and Muthukumaran, K. and Ptaszek, M. and Zaidi, S. H.}, year={2006} }
 @article{zaidi_loewe_clark_jacob_lindsey_2006, title={Nearly chromatography-free synthesis of the A(3)B-porphyrin 5-(4-hydroxymethylphenyl)-10,15,20-tri-p-tolylporphinatozinc(II)}, volume={10}, ISSN={["1520-586X"]}, DOI={10.1021/op0502553}, abstractNote={Rational routes to synthetic porphyrins bearing distinct meso-substituents have typically been implemented at modest scale ( 10:1 ratio (versus 4:1 using EtMgBr), (iii) isolation of the dibutyltin complex of the 1,9-diacyl...}, number={2}, journal={ORGANIC PROCESS RESEARCH & DEVELOPMENT}, author={Zaidi, SHH and Loewe, RS and Clark, BA and Jacob, MJ and Lindsey, JS}, year={2006}, pages={304–314} }
 @article{zaidi_fico_lindsey_2006, title={Investigation of streamlined syntheses of porphyrins bearing distinct meso substituents}, volume={10}, ISSN={["1520-586X"]}, DOI={10.1021/op050193g}, abstractNote={The use of porphyrins in fundamental studies and diverse applications requires facile access to ample quantities of material in pure form. The existing conditions for the condensation of a dipyrromethane plus a dipyrromethane−dicarbinol employ 2.5 mM reactants and afford ∼30% yields with no detectable scrambling. Large-scale syntheses require condensation and oxidation conditions that function at higher concentrations. Thirty-one acids (plus additives) have been examined for reactions at 25 mM reactants using the synthesis of a trans-A2B2-porphyrin as a model. The porphyrin was formed in ∼20% yield upon condensation in CH2Cl2 at room temperature using (1) Sc(OTf)3 (3.2 mM) + 2,6-di-tert-butylpyridine (32 mM), or (2) Zn(OTf)2 (10 mM). Nine porphyrins were prepared in this manner in yields of 15−22% with no detectable scrambling, whereas three other porphyrins afforded low levels of scrambling and/or lower yields (8−14%). Conditions for the oxidation also have been investigated. The reaction of 5-mesityldip...}, number={1}, journal={ORGANIC PROCESS RESEARCH & DEVELOPMENT}, author={Zaidi, SHH and Fico, FM and Lindsey, JS}, year={2006}, pages={118–134} }
 @article{muthukumaran_zaidi_yu_thamyongkit_calder_sharada_lindsey_2005, title={Synthesis of dipyrrin-containing architectures}, volume={9}, ISSN={["1099-1409"]}, DOI={10.1142/S108842460500085X}, abstractNote={ Dipyrrins are valuable precursors to dyes [dipyrrinatoboron difluoride, bis(dipyrrinato)-zinc(II) complexes] and serve as ligands in a variety of self-assembled materials. Six new dipyrrin-containing architectures have been synthesized. The architectures include bis(dipyrrinato) complexes containing copper(II) or palladium(II), a dipyrrin bearing a protected phosphonic acid unit, a porphyrin bearing two dipyrrins in a trans configuration, a linear diphenylethyne-linked dipyrromethane-dipyrrin building block, and a triad composed of two zinc porphyrins joined via an intervening bis(dipyrrinato)copper(II) complex. Two porphodimethenatozinc complexes were prepared and found to have Φ f  ≤ 0.002 (in toluene at room temperature), which is substantially less than the analogous bis(dipyrrinato)zinc complexes. Taken together, the syntheses described herein should broaden access to dipyrrins for use as complexation motifs in supramolecular chemistry and as pigments in light-harvesting applications. }, number={10-11}, journal={JOURNAL OF PORPHYRINS AND PHTHALOCYANINES}, author={Muthukumaran, Kannan and Zaidi, Syeda Huma H. and Yu, Lianhe and Thamyongkit, Patchanita and Calder, Matthew E. and Sharada, Duddu S. and Lindsey, Jonathan S.}, year={2005}, pages={745–759} }
 @article{zaidi_muthukumaran_tamaru_lindsey_2004, title={9-Acylation of 1-acyldipyrromethanes containing a dialkylboron mask for the alpha-acylpyrrole motif}, volume={69}, ISSN={["0022-3263"]}, DOI={10.1021/jo048587d}, abstractNote={1,9-Diacyldipyrromethanes are important precursors to porphyrins, yet synthetic access remains limited owing to (1) poor conversion in the 9-acylation of 1-acyldipyrromethanes and (2) handling difficulties because acyldipyrromethanes typically streak upon chromatography and give amorphous powders upon attempted crystallization. A reliable means for converting a dipyrromethane to a 1-acyldipyrromethane−dialkylboron complex was recently developed, where the dialkylboron (BR2) unit renders the complex hydrophobic and thereby facilitates isolation. Herein a refined preparation of 1,9-diacyldipyrromethanes is presented that employs the 1-acyldipyrromethane−BR2 complex as a substrate for 9-acylation. The dialkylboron unit provides protection for the α-acylpyrrole unit. 9-Acylation requires formation of the pyrrolyl−MgBr reagent and the presence of 1 equiv of a nonnucleophilic base to quench the proton liberated upon α-acylation. Reaction of the 1-acyldipyrromethane−BR2 complex (1 equiv) with mesitylmagnesium br...}, number={24}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Zaidi, SHH and Muthukumaran, K and Tamaru, S and Lindsey, JS}, year={2004}, month={Nov}, pages={8356–8365} }