4-HYDROXY COUMARINS,COMPOSITIONS CONTAINING THEM AND METHOD OF USE

摘要

1458670 3-Tetrahydronaphthyl-4-hydroxycoumarin derivatives WARD BLENKINSOP & CO Ltd 23 May 1974 [23 May 1973 25 May 1973 1 March 1974] 24685/73 25264/73 and 9450/74 Heading C2C Novel compounds of the Formula I wherein R1 and R2 are the same or different and are hydrogen, halogen, alkyl or alkoxy, R3 is an (R4) m substituted phenyl where m is 1 or 2 and R4 is the same or different and is halogen, alkyl, alkoxy, cycloalkyl, aralkyl or optionally halogen substituted phenyl or phenoxy, may be prepared by reacting 4-hydroxy coumarin with a compound of the Formula III or IV wherein hal is halogen and optionally separating isomers. 1 - Bromo - 3 - p - diphenyltetralin is prepared by bromination of 3-p-diphenyltetralin-1-ol. 3 - p - Diphenyltetralin - 1 - ol is prepared by reduction of benzyl p-biphenylketone to yield α - benzyl - p . phenylbenzylalcohol followed by chlorination or bromination to yield α-benzyl-pphenylbenzylbromide or chloride which with sodium diethyl malonate followed by hydrolysis yields (1 - p - biphenyl - 2 - phenylethyl)malonic acid which may be decarboxylated to yield 3- p-diphenyl-4-phenyl butyric acid. Both of the above acids cyclize with polyphosphoric acid to yield 3-p-biphenyl tetralin-1-one which is reduced to the required compound. 3 - p - Diphenyl - 4 - phenylbutyric acid is also prepared by reacting benzyl p-biphenyl ketone with ethylbromoacetate and zinc (Reformatsky) to yield ethyl-3-p-biphenyl-3-hydroxy-4-phenyl butyrate which is dehydrated and hydrolysed to 3-benzyl-3-p-biphenyl acrylic acid which is hydrogenated to give the required butyric acid. Compositions of compounds of the Formula I with a carrier may be used as a rodenticide. The compounds are also useful in human medicine.