GB1377233A - Substituted para-fluorophenols and their use as cyan couplers - Google Patents

Abstract

1377233 Substituted para - fluorophenols EASTMAN KODAK CO 17 Feb 1972 [18 Feb 1971] 7336/72 Heading C2C [Also in Division G2] The invention comprises compounds of formula wherein each R<SP>1</SP> and R<SP>3</SP> is hydrogen or a C 1-4 alkyl group; R<SP>2</SP> is an aryloxyalkylcarbonamido group, the aryl group of which may be substituted; R<SP>4</SP> is an aryl- or alkyl-carbonamido group or an arylureido group, the aryl and alkyl groups of which may be substituted; and L is a group of formula -NH-CO-Ph-CO-NH-, -NHCONH-, -NHCO(CH 2 ) 9 -CO-NH- or -NH-CO-Ph-SO 2 -NH-, wherein Ph is a 1,4-phenylene group and q is 1 to 7. The above compounds may be obtained from pfluorophenol through the following reaction steps:-The p-fluorophenol is converted in the 2-position to a nitro derivative, this intermediate is converted to the corresponding 2- methyl-5-fluorobenzoxazole by catalytic reduction followed by cyclization with triethylorthoacetate. The resulting 2-methyl-5-fluorobenzoxazole is then nitrated with an HNO 3 and H 2 SO 4 acid mixture and hydrolysed to obtain 2-amind-4-fluoro-5-nitro phenol. This intermediate is reacted with an equimolar amount of an appropriate acid chloride in a solvent for 1 hour at room temperature and then poured into a dilute solution of HCl at about 0‹ C. The resulting 2-acylamino-4-fluoro-5-nitrophenol is then finally converted to the desired 2-acylamino - 5 - amino - 4 - fluorophenol by catalytic hydrogenation. Example I describes the preparation of 2-pentafluorobenzamido-4-fluoro- 5-[α-(2,4 - di - t - amylphenoxy) hexanamido] phenol. In its preparation the following intermediates are isolated: 2-nitro-4-fluorophenol; 2 - methyl - 5 - fluorobenzoxazole; 2 - methyl - 5- fluoro - 6 - nitrobenzoxazole; 2 - amino - 4- fluoro - 5 - nitrophenol; 2 - pentafluorobenzamido - 4 - fluoro - 5 - nitrophenol and 2 - pentafluorobenzamido - 5 - amino - 4 - fluorophenol.