- Formation of 2,6-Naphthalenedicarboxylic Acid by the Co-Mn-Br-Catalyzed Autoxidation of 2,6-Diethylnaphthalene in Acetic Acid
-
In order to elucidate the reaction mechanism and the optimum reaction conditions for the formation of 2,6-naphthalenedicarboxylic acid (NDCA), the Co(OAc)2-Mn(OAc)2-NaBr-catalyzed oxidation of 2,6-diethylnaphthalene by molecular oxygen was carried out in acetic acid.The oxidation of the ethyl groups to carboxyl groups proceeded mainly via groups and partly via 1-hydroxyethyl and 1-acetoxyethyl groups.A synergistic catalytic effect due to Co and Mn acetates was observed not only on the rate of oxidation but also on the selective formation of NDCA.The rate of oxidation was strongly retarded at higher concentrations of the substrate, showing that the naphthalene nucleus terminates the chain reaction step of the oxidation.A high concentration of metal catalyst resulted in an increase of acetoxyethylnaphthoic acid.At the optimum reaction conditions, a nearly 90percent yield of NDCA was obtained along with small amounts of substituted naphthoic and trimellitic acids.The differences in the yield of NDCA from 2,6-dimethyl, 2,6-diethyl, and 2,6-diisopropylnaphthalenes were compared under similar reaction conditions and are discussed.
- Kamiya, Yoshio,Hama, Takashi,Kijima, Ichiro
-
-
Read Online
- ARYLCARBOXAMIDES AND USES THEREOF
-
The present disclosure is directed to compounds of formula (I): or a pharmaceutically acceptable salt, solvate or solvate of the salt thereof. Compounds of formula (I) are inhibitors of NOX4 and are useful in the treatment of fibrotic diseases such as scleroderma; lung disease, such as pulmonary fibrosis including idiopathic pulmonary fibrosis (IPF); heart disease, such as heart failure due to ischaemic heart disease, valvular heart disease and hypertensive heart disease, diabetic cardiomyopathy and hypertension; liver disease, such as cirrhosis of the liver; and kidney disease, such as progressive kidney disease glomerulonephritis and diabetic nephropathy; and eye disease such as diabetic retinopathy; skin or subcutaneous scarring, such as keloids, adhesions, hypertrophic scarring or cosmetic scarring; or as an adjuvant or anti-fibrotic in pancreatic cancer to increase chemotherapeutic drug penetration by reducing the density of the connective tissue stroma.
- -
-
Paragraph 0184
(2017/12/13)
-