Tetraphenylporphine complexes

Cobalt (II) meso-5.10,15,20-tetraphenylporphine complex [14172-90-8] M 671.7. Brown crystals from Et20 or CHCl3-MeOH (cf iron chloride complex). Recrystd by extraction (Soxhlet) with CgHg. Sol in most organic solvents except MeOH and pet ether. [UV, IR J Am Chem Soc 70 1808 7948 81 5111 7959.]... 

Formation of a rhodium tetraphenylporphine complex having a Rh-phenyl a-bond was reported by Fleischer and Lavalles 17K... 

Cobalt (n) 10,15,20-tetraphenylporphine complex [14172-90-8] M 671.7. It yields brown crystals... 

Saitoh et al. [152] separated seven rare-earth ions (Nd(III), Gd(III), Tb(III), Dy(ni), Ho(ni), Er(III), Lu(III)) as their tetraphenylporphine complexes using a C 8 column (2 = 555 nm) and a 90/10 methanol/water (0.5% acetylacetone with 0.68% triethylamine) mobile phase. Injections of 10 pL of 0.1 mM metal-complex solutions were made. The Nd(III) complex was stable for less than one hour in any of the solvents methanol, acetone, acetonitrile, or dichloromethane. Elution was complete in <15 min. Similarly, the tetraphenylporphine complexes of VO(IV), Cu(II), Ni(II), Zn(II), and Pd(II) were resolved on a C g column (X = 420nm) using a metha-nol/octane mobile phase where octane was present at less than 0.1 mole fraction [153]. (It should be noted that 0.1 mole fraction octane is equivalent to 21% in methanol.) A 1 pL injection of a standard containing 4 x 10 M metal complex was readily detected. 

K. Saitoh, Y. Shibata, and N. Suzuki. Factors influencing the retention of rare earth— tetraphenylporphine complexes in reversed-phase high-performance liquid chromatography. Journal of Chromatography A 542 351-363,1991. 

Iron (III) meso-5,10,15,20-tetraphenylporphine chloride complex [16456-81-8] M 704.0. Crystallise by extraction from a thimble (Soxhlet) with CHCI3. Concentrate the extract to ca lOmL and add ca 80mL of hot MeOH. Dark blue crystals separate on cooling. It can be recrystallised several times from CHCl3-MeOH. Avoid prolonged heating. It is quite soluble in organic solvents but insoluble in pet ether. [J Am Chem Soc 70 1808 1948 UV 73 4315 7957.]... 

Pyridines are also well known as ligands in transition metal complexes, and if the equilibrium constants for the formation of such complexes can be related to base strength, it is expected that such constants would follow the Hammett equation. The problem has been reviewed,140 and a parameter S, formulated which is a measure of the contribution of the additional stabilization produced by bond formation to the stabilization constants of complexes expressed in terms of a.141 The Hammett equation has also been applied to pyridine 1 1 complexation with Zn(II), Cd(II), and Hg(II) a,/3,y,<5-tetraphenylporphins,142 143 the a values being taken as measures of cation polarizing ability. Variation of the enthalpy of complexation for adducts of bis(2,4-pentanediono)-Cu(II) with pyridines plotted against a, however, exhibited a curved relationship.144... 

Another example of compounds with the fixed mutual location of porphyrin and quinone are the porphyrin-quinone compounds with a rigid bridge. Charge photoseparation in P-L-Q molecules in which L is the trip-ticene bridge, P is tetraphenylporphin, TPP, or its zinc complex, and Q is benzoquinone, BQ, naphthoquinone, NQ, or anthraquinone, AQ, has been studied [55]. The distance between the centres of P and Q fragments in these... 

Catalytic reactions were performed in CH2C12 under an 02 atmosphere Zn was used as an electron source and acetic acid as a proton donor (14). Under these reaction conditions ([2] [substrate] = 1 125), the production of adamantan-l-ol (248%), adamantan-2-ol (50%), and adamantan-2-one (108%) was observed. With cyclohexene as substrate, a mixture of cyclohexanol (54%), cyclohexanone (73%), and cyclohexene oxide (20%) was generated. In a similar experiment with cyclohexane, cyclohexanol (99%), and cyclohexanone (84%) were obtained. The product distribution is inconsistent with a free radical process for ada-mantane, the 3°/2° carbon reactivity ratio is 2.2. Control experiments demonstrated that both Zn dust and acetic acid were necessary, whereas larger quantities of acetic acid quenched the reaction (Table II). This may be due to the acidolysis of the n-oxo bond. Simple monomeric complexes such as FeClTPP (TPP is tetraphenylporphin), Fe(acac)3 (acac is acetylacetonate), and [Fe(HBpz3)2]+, 3, were inactive as catalysts under identical conditions. Furthermore, [Fe3+(Salen)]20, 1, did not show any reactivity. 

The iron(I) anion [Fc(TPP)] (TPP = tetraphenylporphine dianion) is produced243 by the reduction of p-oxo-bis(tetraphenylporphineiron(III)) with Na/ Hg in THF. The product appears to exist in different spin states in THF solution (200-300 K) and frozen THF matrix at 77 K. A recent study, however,244 is unequivocal about the d1 Fe1 nature of the complex in the presence of pyridine. 

Another interesting synthesis of fused-ring thiiranes was reported by Weinkotz and co-workers in a sulfur-transfer reaction from 3,3,7,8-tetramethyl-9,10-dioxa-ll-thiatricyclo[6.2.1.0 ]undec-6-en-5-one (a derivative of thiophene endoperoxide) 37 to cyclic olefins under thermolysis conditions, or at low temperature using tetraphenylporphine cobalt(ll) complex as a catalyst (Scheme 56) <1996CC177>. The endoperoxide was prepared by photo-oxygenation... 

Re2(CO)io reacts with meso-tetraphenylporphine in decalin under reflux to afford (meso-tetraphenylporphinato)bis tricarbonylrhenium(i) which has been shown by X-ray crystallography to involve the basic structural unit (92). Each Re atom is 142 pm out of the macrocyclic plane. The metal-metal separation of 312.6 pm is rather long for any direct interaction. Similar complexes containing two Re(CO)3 groups or one Re(CO)3 and one Tc(CO)3 group have been prepared with mesoporphyrin IX dimethyl ester. 

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