643-79-8 Usage
Chemical Description
o-Phthalaldehyde is a chemical compound used in organic synthesis and as a fluorescent probe for amino acids.
Description
o-Phthalaldehyde, also known as OPA, is a dialdehyde in which two formyl groups are attached to adjacent carbon centers on a benzene ring. It is a pale yellow crystalline solid with various applications in different industries.
Uses
Used in Chromatography and Electrophoresis:
o-Phthalaldehyde is used as a precolumn derivatization agent for primary amines and amino acids in high-performance liquid chromatography (HPLC) separation and capillary electrophoresis. The fluorescent derivative formed can be detected by reverse-phase HPLC, allowing for the quantitation of amines and sulfhydryls in the presence of excess sulfhydryl or amine, respectively.
Used in Flow Cytometry:
o-Phthalaldehyde is utilized for flow cytometric measurements of protein thiol groups, providing valuable insights into protein structure and function.
Used in Disinfection:
o-Phthalaldehyde serves as a high-level disinfectant, particularly for heat-sensitive medical and dental equipment such as endoscopes and thermometers. It has emerged as a safe and effective alternative to glutaraldehyde, with better sterilizing power, speed, stability, and lower toxicity. It can effectively kill mycobacterium within 5 minutes, reducing the bacterial count by 5 logarithmic values.
Used in Biotechnological Applications:
o-Phthalaldehyde is employed for precolumn derivatization of amino acids for HPLC separation and for flow cytometric measurements of protein thiol groups. It is also used for the fluorometric determination of histamine, histidine, and other amino acids, as well as for cholesterol assays in the picomole range.
Used in Pharmaceutical Analysis:
Phthaldialdehyde has been used in the preparation of o-phthaldialdehyde reagents for analyzing gentamycin content, determining the degree of hydrolysis of milk proteins, measuring free amino acids in milk samples using the o-phthaldialdehyde/N-acetyl-L-cysteine (OPA/NAC) assay, and in the derivatization of putrescine samples.
Preparation
o-Phthalaldehyde is a high-level chemical disinfectant that is commonly used for disinfection of dental and medical instruments as an alternative to glutaraldehyde, which is a known skin and respiratory sensitizer.
A variety of processes for manufacturing o-phthalaldehyde have been reported in the literature.
o-Phthalaldehyde is produced by heating pure benzaldehyde and chloroform with potassium hydroxide solution. The resulting solution is further acidified with hydrochloric acid and cooled to yield a colorless powder of o-phthalaldehyde.
It is also produced by ozonization of naphthalene in alcohol followed by catalytic hydrogenation.
Catalytic oxidation of various chemicals is also used in manufacturing o-phthalaldehyde. o-Phthalaldehyde can be manufactured by oxidation of phthalan by nitrogen monoxide in acetonitrile with N-hydroxyphthalimide as the catalyst to yield 80% to 90%.
Synthesis Reference(s)
Journal of the American Chemical Society, 73, p. 1668, 1951 DOI: 10.1021/ja01148a076Tetrahedron Letters, 27, p. 1793, 1986 DOI: 10.1016/S0040-4039(00)84377-4
Flammability and Explosibility
Notclassified
Potential Exposure
The primary routes of human exposure to o-phthalaldehyde are by inhalation and through the skin, which may occur through accidental or occupational exposures. Along with its increasing popularity as a chemical sterilizer, o-phthalaldehyde has many applications in analytical methods and in diagnostic kits. o-Phthalaldehyde is also used as an intermediate in the synthesis of pharmaceuticals and as a reagent in the tanning industry, hair colorings, wood treatment, and antifouling paints. o-Phthalaldehyde was approved for use as an indoor antimicrobial pesticide in 1997; however, it is no longer registered with the United States Environmental Protection Agency (USEPA) for this use.
Carcinogenicity
No information on the carcinogenicity of o-phthalaldehyde in experimental animals or humans was found in a review of the literature.
Check Digit Verification of cas no
The CAS Registry Mumber 643-79-8 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 6,4 and 3 respectively; the second part has 2 digits, 7 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 643-79:
(5*6)+(4*4)+(3*3)+(2*7)+(1*9)=78
78 % 10 = 8
So 643-79-8 is a valid CAS Registry Number.
InChI:InChI=1/C8H6O2/c9-5-7-3-1-2-4-8(7)6-10/h1-6H
643-79-8Relevant articles and documents
Smart solution chemistry: Prolonging the lifetime of ortho-phthalaldehyde disinfection solutions
Brewer, Bobby N.,Mead, Keith T.,Pittman Jr., Charles U.,Lu, Kaitao,Zhu, Peter C.
, p. 361 - 363 (2006)
The oxidation of ortho-phthalaldehyde to phthalic acid in aqueous solutions can be remedied by the addition of various cyclic acetals, which, when reacted with phthalic acid, yields ortho-phthalaldehyde, thus prolonging the lifetime of the ortho-phthalaldehyde disinfection solution.
Oxidaition of cyclic benzylic ethers by an electronically tuned nitroxyl radical
Furuta, Takumi,Hamada, Shohei,Kawabata, Takeo,Kobayashi, Yusuke,Yano, Kyoko
supporting information, (2021/10/04)
The reactivity of an electronically tuned nitroxyl radical catalyst for the oxidation of cyclic benzylic ethers has been investigated. The oxidation of phthalan resulted in oxidative cleavage of the saturated ring to give an aromatic dialdehyde. Additionally, oxidation of isochromans afforded isochromanones, which are often seen in natural products, in a rapid manner.
Synthesis of new Zn (II) complexes for photo decomposition of organic dye pollutants, industrial wastewater and photo-oxidation of methyl arenes under visible-light
Ahemed, Jakeer,Bhongiri, Yadagiri,Chetti, Prabhakar,Gade, Ramesh,Kore, Ranjith,Pasha, Jakeer,Pola, Someshwar,Rao D, Venkateshwar
, (2021/07/28)
Synthesis of new Schiff's base Zn-complexes for photo-oxidation of methyl arenes and xylenes are reported under visible light irradiation conditions. All the synthesized new ligands and Zn-complexes are thoroughly characterized with various spectral analyses and confirmed as 1:1 ratio of Zn and ligand with distorted octahedral structure. The bandgap energies of the ligands are higher than its Zn-complexes. These synthesized new Zn(II) complexes are used for the photo-fragmentation of organic dye pollutants, photodegradation of food industrial wastewater and oxidation of methyl arenes which are converted into its respective aldehydes with moderate yields under visible light irradiation. The photooxidation reaction dependency on the intensity of the visible light was also studied. With the increase in the dosage of photocatalyst, the methyl groups are oxidized to get aldehydes and mono acid products, which are also identified from LC-MS data. Finally, [Zn(PPMHT)Cl] is with better efficiency than [Zn(PTHMT)Cl] and [Zn(MIMHPT)Cl] for oxidation of methyl arenes is reported under visible-light-driven conditions.
Efficient synthesis of 4-substituted-ortho-phthalaldehyde analogues: Toward the emergence of new building blocks
Moitessier, Clémence,Rifai, Ahmad,Danjou, Pierre-Edouard,Mallard, Isabelle,Cazier-Dennin, Francine
, p. 721 - 726 (2019/04/17)
4-Methoxy-ortho-phthalaldehyde and 4-hydroxy-ortho-phthalaldehyde are potentially useful molecules for fluorimetric analysis of a variety of amines and for the elaboration of complex molecular architectures. Nevertheless, literature generally describes their synthesis in very low yield (below 5%), mainly due to the inefficiency of the last oxidation step. In this paper, we report a reliable synthesis of 4-substituted-ortho-phthalaldehyde analogues in 51% overall yield owing to the addition of a protecting step of the unstable key intermediate 4,5-dihydroisobenzofuran-5-ol. Oxidation and deprotection steps were also studied in order to provide an effective availability of these two dialdehyde compounds that may increase their future applications.