Synthesis of meso-substituted porphyrins

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Synthesis of meso-substituted porphyrins

• Mariusz Tasior

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Rothemund method in 1935...
Rothemund, P., J. Am. Chem. Soc. 1935, 57, 2010.
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Rothemund method in 1935...
First report about effects of metals in
pyrrole-aldehyde condensation Ball, R. H. et al.
J. Am. Chem. Soc. 1946, 68, 2278.
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Some general considerations...
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Some general considerations...
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Adler method
Adler, A.D. Longo, F. R. Shergalis, W., J. Am.
Chem. Soc. 1964, 86, 3145.
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Scope of Adler method
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Scope of Adler method
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Mixed-aldehyde condensation
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Mixed-aldehyde condensation
Leznoff, C. C. Svirskaya, P.I, Angew. Chem. In.
Ed. 1978, 12, 947.
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Lindsey method 1979-...
Lindsey, J. S., Hsu, H. C., Schreiman, I. C.
Tetrahedron Lett. 1986, 27, 4969. Lindsey, J. S.,
Schreiman, I. C., Hsu, H. C., Kearney, P. C.,
Marguerettaz, A. M. Tetrahedron Lett. 1986, 27,
4969. Acid cocatalysis, salt effect Lindsey et
al. JPP, 2001, 5, 681
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Scope of Lindsey method
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Comparison of synthetic methods
Rothemund Adler Lindsey
Solvent Pyridine Propionic acid Acetic acid RCOOHbenzene DCM Chloroform
Temperature 140-220ºC 141ºC 25ºC
Catalyst - Same as solvent TFA BF3-etherate Clays, other acids
Concentration 0.4-3.6M 0.3-0.1M 0.1-0.001M
Reaction time 24-48hr 1hr 1hr
Workup Separate crystals Filter crystals Chromatography
Yield lt10 20 40
Scope very narrow modest broad
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Routes to specific classes of meso-substituted
porphyrins
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Trans-A2B2-porphyrins
For dipyrromethane synthesis Lindsey, J. S. et
al. Org. Process Res. Dev. 2003, 7, 799. For
condensation conidtions and scrambling Lindsey,
J. S. et al. J. Org. Chem. 1999, 8, 2864
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Scrambling
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Porphyrins bearing up to 4 different meso
substituents
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Thank you...