Synthesis and characterization of new isomeric water-soluble porphyrins. Tetra(2-N-methylpyridyl)porphine and tetra(3-N-methylpyridyl)porphine. [Acid solvolysis of zinc porphyrin isomers]
Preparation of a series of water soluble porphyrins, tetra(2-N-methylpyridyl)porphine (TMpyP(2)), tetra(3-N-methylpyridyl)porphine (TMpyP(3)), and tetra(4-N-methylpyridyl)porphine (TMpyP(4)) is described. TmpyP(4) precipitates immediately from 2.0M HClO/sub 4/, TMpyP(3) requires 24h at O/sup 0/C for precipitation, and TMpyP(2) remains in solution. The acid solvolysis behavior of the zinc porphyrin(ZrP)isomers was studied in 1.0M acid solutions at 25/sup 0/C; and under pseudo-first-order conditions, the reactions were first order in ZnP. Different rates of acid solvolysis in HCl and HNO/sub 3/ for TpyP(4) are shown to arise from different rate laws. Substituted deuteroporphyrins were used in the acid solvolysis studies, and the rates of solvolysis were found to be faster the higher the basicity of the free porphyrin toward protons. The observed zinc porphyrin kinetic solvolysis order, TpyP(3) greater than TpyP(4) greater than TpyP(2), parallels the electrochemical reduction potentials of the porphyrins in 1.0M HCl. (BLM)
- Research Organization:
- Howard Univ., Washington, DC
- OSTI ID:
- 7345319
- Journal Information:
- Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 15:9; ISSN INOCA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
400302 -- Organic Chemistry-- Isotope Effects-- (-1987)
CARBOXYLIC ACIDS
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
DEUTERIUM
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROGEN ISOTOPES
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LIGHT NUCLEI
NUCLEI
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANOMETALLIC COMPOUNDS
PORPHYRINS
REACTION KINETICS
STABLE ISOTOPES
SYNTHESIS
ZINC COMPOUNDS