Phenanthroline
Names | |
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Preferred IUPAC name
1,10-Phenanthroline[1] | |
Identifiers | |
CAS Number
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3D model (JSmol)
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126461 | |
ChEBI | |
ChEMBL |
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ChemSpider | |
DrugBank | |
ECHA InfoCard | 100.000.572 |
EC Number |
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Gmelin Reference
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4040 |
KEGG | |
PubChem CID
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RTECS number |
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UNII |
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UN number | 2811 |
CompTox Dashboard (EPA)
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InChI
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Properties | |
Chemical formula
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C12H8N2 |
Molar mass | 180.21 g/mol |
Appearance | colourless crystals |
Density | 1.31 g/cm3 |
Melting point | 118.56 °C (245.41 °F; 391.71 K)[2] |
Boiling point | 409.2 [2] |
high[2] | |
Solubility in other solvents | acetone, ethanol[2] |
Acidity (pKa) | 4.84 (phenH+)[3] |
Hazards | |
Main hazards | mild neurotoxin, strong nephrotoxin, and powerful diuretic |
GHS labelling: | |
Pictograms
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Signal word
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Danger |
H301, H410 | |
Precautionary statements
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P264, P270, P273, P301+P310, P321, P330, P391, P405, P501 |
Related compounds | |
Related compounds
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2,2'-bipyridine ferroin phenanthrene |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
what is ?) | (|
Infobox references | |
Phenanthroline (phen) is a heterocyclic organic compound. It is a white solid that is soluble in organic solvents. It is used as a ligand in coordination chemistry, forming strong complexes with most metal ions.[4][5] It is often sold as the monohydrate.
Synthesis[]
Phenanthroline may be prepared by two successive Skraup reactions of glycerol with o-phenylenediamine, catalyzed by sulfuric acid, and an oxidizing agent, traditionally aqueous arsenic acid or nitrobenzene.[6] Dehydration of glycerol gives acrolein which condenses with the amine followed by a cyclization.
Coordination chemistry[]
In terms of its coordination properties, phenanthroline is similar to 2,2'-bipyridine (bipy) but binds metals more tightly since the chelating nitrogen donors are preorganized. Phenanthroline is however a weaker donor than bipy.[7]
Many homoleptic complexes are known. Particularly well studied is [Fe(phen)3]2+, called "ferroin." It was used for the photometric determination of Fe(II).[8] It is used as a redox indicator with standard potential +1.06 V. The reduced ferrous form has a deep red colour and the oxidised form is light-blue.[9] The pink complex [Ni(phen)3]2+ has been resolved into its Δ and Λ isomers.[10] Copper(I) forms [Cu(phen)2]+, which is luminescent.[11][12]
Bioinorganic chemistry[]
The ferroin analogue [Ru(phen)3]2+ has long been known to be bioactive.[13]
1,10-Phenanthroline is an inhibitor of metallopeptidases, with one of the first observed instances reported in carboxypeptidase A.[14] Inhibition of the enzyme occurs by removal and chelation of the metal ion required for catalytic activity, leaving an inactive apoenzyme. 1,10-Phenanthroline targets mainly zinc metallopeptidases, with a much lower affinity for calcium.[15]
Related phen ligands[]
A variety of substituted derivatives of phen have been examined as ligands.[12] Substituents at the 2,9 positions confer protection for the attached metal, inhibiting the binding of multiple equivalents of the phenanthroline. Phen itself form complexes of the type [M(phen)3]Cl2 when treated with metal dihalides (M = Fe, Co, Ni). By contrast, neocuproine and bathocuproine form 1:1 complexes such as [Ni(neo/batho-cuproine)Cl2]2.[16]
ligand | pKa | comment/alt. name | illustration |
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1,10-phenanthroline | 4.86 | phen | |
2,2'-bipyridine | 4.30 | less basic than phen | |
5-nitro-1,10-phenanthroline | 3.57 | ||
2,9-dimethyl-1,10-phenanthroline | unknown | neocuproine | |
4,7-dimethyl-1,10-phenanthroline | 5.97 | ||
4,7-diphenyl-1,10-phenanthroline | unknown | bathophenanthroline | |
5,6-dimethyl-1,10-phenanthroline | 5.20 | ||
3,4,7,8-tetramethylphenanthroline | 6.31 | 3,4,7,8-Me4phen | |
4,7-dimethoxy-1,10‐phenanthroline | 6.45 | 4,7-(MeO)2phen[18] |
As an indicator for alkyllithium reagents[]
Alkyllithium reagents form deeply colored derivatives with phenanthroline. The alkyllithium content of solutions can be determined by treatment of such reagents with small amounts of phenanthroline (ca. 1 mg) followed by titration with alcohols to a colourless endpoint.[19] Grignard reagents may be similarly titrated.[20]
See also[]
- Ferroin – Complex of Fe2+ by ortho-phenantroline
References[]
- ^ Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 211. doi:10.1039/9781849733069-FP001. ISBN 978-0-85404-182-4.
- ^ a b c d Haynes, p. 3.444
- ^ Haynes, p. 5.95
- ^ Luman, C.R. and Castellano, F.N. (2003) "Phenanthroline Ligands" in Comprehensive Coordination Chemistry II. Elsevier. ISBN 978-0-08-043748-4.
- ^ Sammes, Peter G.; Yahioglu, Gokhan (1994). "1,10-Phenanthroline: A versatile ligand". Chemical Society Reviews. 23 (5): 327. doi:10.1039/cs9942300327.
- ^ Halcrow, Barbara E.; Kermack, William O. (1946). "43. Attempts to find new antimalarials. Part XXIV. Derivatives of o-phenanthroline (7 : 8 : 3′ : 2′-pyridoquinoline)". J. Chem. Soc.: 155–157. doi:10.1039/jr9460000155. PMID 20983293.
- ^ Teng, Qiaoqiao; Huynh, Han Vinh (2017). "A unified ligand electronic parameter based on C NMR spectroscopy of N-heterocyclic carbene complexes". Dalton Transactions. 46 (3): 614–627. doi:10.1039/C6DT04222H. PMID 27924321.
- ^ Belcher R (1973). "Application of chelate Compounds in Analytical Chemistry". Pure and Applied Chemistry. 34: 13–27. doi:10.1351/pac197334010013. S2CID 44054260.
- ^ Bellér, G. B.; Lente, G. B.; Fábián, I. N. (2010). "Central Role of Phenanthroline Mono-N-oxide in the Decomposition Reactions of Tris(1,10-phenanthroline)iron(II) and -iron(III) Complexes". Inorganic Chemistry. 49 (9): 3968–3970. doi:10.1021/ic902554b. PMID 20415494.
- ^ George B. Kauffman; Lloyd T. Takahashi (1966). Resolution of the tris-(1,10-Phenanthroline)Nickel(II) Ion. Inorg. Synth. Inorganic Syntheses. 5. pp. 227–232. doi:10.1002/9780470132395.ch60. ISBN 9780470132395.
- ^ Armaroli N (2001). "Photoactive Mono- and Polynuclear Cu(I)-Phenanthrolines. A Viable Alternative to Ru(Ii)-Polypyridines?". Chemical Society Reviews. 30 (2): 113–124. doi:10.1039/b000703j.
- ^ a b Pallenberg A. J.; Koenig K. S.; Barnhart D. M. (1995). "Synthesis and Characterization of Some Copper(I) Phenanthroline Complexes". Inorg. Chemistry. 34 (11): 2833–2840. doi:10.1021/ic00115a009.
- ^ Dwyer, F. P.; Gyarfas, Eleonora C.; Rogers, W. P.; Koch, Judith H. (1952). "Biological Activity of Complex Ions". Nature. 170 (4318): 190–191. Bibcode:1952Natur.170..190D. doi:10.1038/170190a0. PMID 12982853. S2CID 6483735.
- ^ Felber, Jean-Pierre; Coombs, Thomas L.; Vallee, Bert L. (1962). "The mechanism of inhibition of carboxypeptidase A by 1,10-phenanthroline". Biochemistry. 1 (2): 231–238. doi:10.1021/bi00908a006. PMID 13892106.
- ^ Salvesen, GS & Nagase, H (2001). "Inhibition of proteolytic enzymes". In Beynon, Rob & Bond, J S (eds.). Proteolytic Enzymes: A Practical Approach. 1 (2nd ed.). Oxford University Press. pp. 105–130. ISBN 9780199636624.
- ^ Preston, H. S.; Kennard, C. H. L. (1969). "Crystal Structure of di-mu-Chloro-sym-trans-Dichloro-Bis-(2,9-Dimethyl-1,10-Phenanthroline)dinickel(II)-2-Chloroform". J. Chem. Soc. A: 2682–2685. doi:10.1039/J19690002682.
- ^ Leipoldt, J.G.; Lamprecht, G.J.; Steynberg, E.C. (1991). "Kinetics of the substitution of acetylacetone in acetylactonato-1,5-cyclooctadienerhodium(I) by derivatives of 1,10-phenantrholine and 2,2′-dipyridyl". Journal of Organometallic Chemistry. 402 (2): 259–263. doi:10.1016/0022-328X(91)83069-G.
- ^ Altman, Ryan A. (2008). "1,10-Phenanthroline, 4,7-Dimethoxy". Encyclopedia of Reagents for Organic Synthesis. eEROS. doi:10.1002/047084289X.rn00918. ISBN 978-0471936237.
- ^ Fagan, Paul J.; Nugent, William A. (1998). "1-Phenyl-2,3,4,5-Tetramethylphosphole". Organic Syntheses.; Collective Volume, 9, p. 653
- ^ Lin, Ho-Shen; Paquette, Leo A. (1994). "A Convenient Method for Determining the Concentration of Grignard Reagents". Synth. Commun. 24 (17): 2503–2506. doi:10.1080/00397919408010560.
Cited sources[]
- Haynes, William M., ed. (2016). CRC Handbook of Chemistry and Physics (97th ed.). CRC Press. p. 3.444. ISBN 9781498754293.
- Redox indicators
- Chelating agents
- Phenanthrolines