4466-59-5

Usage

Chemical Properties

off-white to white powder

Purification Methods

Boil the anhydride in xylene (allowing any vapours which would contain H2O to be removed, e.g. Dean and Stark trap), which causes any acid present to dehydrate to the anhydride, and cool. Recrystallise it from xylene [Villiger Chem Ber 42 3539 1909, Fedoorow Izv Akad Nauk SSSR Otd Khim Nauk 397 1948, Chem Abstr 1585 1948]. [Beilstein 17/11 V 260.]

InChI:InChI=1/C8H2Cl2O3/c9-3-1-2-4(10)6-5(3)7(11)13-8(6)12/h1-2H

Upstream product

• 953065-35-5 3,6-dichloro-phthalic acid monoethyl ester 
• 117-21-5 3-chlorophthalic anhydride 
• 62268-16-0 3,4,6-trichlorophthalic acid 
• 85-44-9 phthalic anhydride 
• 7664-93-9 sulfuric acid 
• 7553-56-2 iodine 
• 7782-50-5 chlorine 
• 100526-88-3 3,6-dichloro-2-(2,5-dichloro-benzoyl)-benzoic acid 
• 117-08-8 tetrachlorophthalic anhydride 
• 632-58-6 tetrachlorophthalic acid 
• 16110-99-9 3,6-dichlorophthalic acid 

Downstream Products

• 101095-35-6 3,6-dichloro-2-(2,5-dimethyl-thiophene-3-carbonyl)-benzoic acid 
• 108798-36-3 3,6-dichloro-2-(3-methyl-thiophene-2-carbonyl)-benzoic acid 
• 114798-85-5 N-[4-(2-Butyl-4-chloro-5-methoxymethyl-imidazol-1-ylmethyl)-phenyl]-3,6-dichloro-N-methyl-phthalamic acid 
• 114798-51-5 N-[4-(2-Butyl-4-chloro-5-methoxymethyl-imidazol-1-ylmethyl)-phenyl]-3,6-dichloro-phthalamic acid 
• 52043-46-6 4,7-dichloro-3H-isobenzofuran-1-one 
• 860596-93-6 3,6-dichloro-2-(4-chloro-3-methyl-benzoyl)-benzoic acid 
• 861531-05-7 3,6-dichloro-2-(1-hydroxy-[2]naphthoyl)-benzoic acid 

Relevant academic research and scientific papers

Synthetic method

A process for the preparation of the compound AQ4 of formula 3: or a salt or N-oxide thereof, includes the step:

A large-scale synthesis of the bioreductive drug 1,4-bis{[2-(dimethylamino)ethyl]amino}-5,8-dihydroxyanthracene-9,10-dione bis-N-oxide (AQ4N)

A large-scale synthesis of the bis-bioreductive drug 1,4-bis{[2-(dimethylamino)ethyl]amino}-5,8-dihydroxy-anthracene-9,10-dione bis-N-oxide (AQ4N) has been developed. This six-step synthesis provides AQ4N in 20% overall yield from readily available tetrachlorophthalic anhydride. The key step was a KF-NaF-mediated conversion of 3,6-dichlorophthalic anhydride to 3,6-difluorophthalic anhydride, which could be achieved in 77% yield on a 100 g scale. A trace impurity in AQ4N was determined (by LC-MS and independent synthesis) to be the mono-N-oxide 1-amino-4-[2-(dimethylamino)ethyl]amino-5,8-dihydroxyanthracene-9,10-dione N-oxide. This is formed spontaneously from AQ4N under a number of conditions, including during HPLC on reversed-phase columns. The Royal Society of Chemistry 1999.

Cyclic Imides. 16. Hydroxy and Methoxy Derivatives of Aminophthalimide and Phthalhydrazide

Treatment of N-alkyl derivatives of 3,6-dichlorophthalimide and 4,5-dichlorophthalimide with potassium nitrite gave 3-hydroxy-6-nitro- and 4-hydroxy-5-nitrophthalimides.The potassium salts of these phenols were alkylated by dialkyl sulfates.The products were reduced to the 3-amino-6-alkoxy- and 4-amino-5-alkoxyphthalimides, and the fluorescence emission spectra of these products were measured.Hydrazinolysis of the phthalimides in a toulene medium gave phthalhydrazides.The luminescence spectra of several aminophthalhydrazides were measured.The infrared and proton magnetic resonance spectra of these and of some nitrophthalhydrazides were measured and aspects of these spectra characteristic of phthalhydrazides were identified.

Benzocyclobutenes. Part 4. Synthesis of Benzocyclobutene-1,2-diones by Pyrolytic Methods

Oxidation of the cyclic hydrazides prepared from phthalic anhydrides in the presence of anthracene gives the corresponding Diels-Alder adducts which, on flash vacuum pyrolysis, give benzocyclobutene-1,2-dione (BBD) and its 4-chloro, 3,6- and 4,5-dichloro, 4,5-dibromo, and 4,5-dimethyl derivatives in 75-98percent yield.Cyclobuta- and cyclobuta-naphthalene-1,2-dione as well as cyclobuta- and cyclobuta-pyridine-1,2-dione have been prepared similarly; the last three of these diones are very unstable.Cyclobutanaphthalene-1,2-dione has also been made by pyrolysis of benzindene-1,2,3-trione.Attempts to make thiophen and furan analogues of BBD from appropriate anthracene adducts failed as did attempts to make tetrachloro- and tetrabromo-derivatives of BBD by the pyrolysis of tetrahalogenophthalimidosulphoximides.