Organic compounds -- part of the class 532-570 series – Organic compounds – Amino nitrogen containing
Patent
1987-11-25
1989-07-04
Willis, Prince E.
Organic compounds -- part of the class 532-570 series
Organic compounds
Amino nitrogen containing
564 95, 564 96, 564 99, 558424, C07C14374
Patent
active
048452858
ABSTRACT:
A process for preparing a compound of formula (II): ##STR1## or a tautomer or salt thereof in substantially pure form wherein R.sup.1 is C.sub.1-6 alkyl optionally substituted by one or more halogen atoms; R.sup.3 is hydrogen, fluorine, chlorine, bromine or iodine, C.sub.1-6 alkyl, trifluoromethyl or a cyano group; R.sup.4 is hydrogen, fluorine, chlorine, bromine, iodine or trifluoromethyl; R.sup.5 is fluorine, chlorine, bromine, iodine or trifluoromethyl; and R.sup.6 is hydrogen or C.sub.1-4 alkyl; which process comprises nitrating a compound of formula (III): ##STR2## or a salt thereof wherein R.sup.1, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are as defined above, in a solvent which is resistant to nitration under the desired reaction conditions and suitable for purification of the product of formula (II), heating the resultant solution to a temperature sufficient to at least partially dissolve the desired product and impurities and cooling the solution to precipitate the compound of formula (II) in substantially pure form.
REFERENCES:
patent: 3856895 (1974-12-01), Moore et al.
patent: 4005102 (1977-01-01), Cook et al.
patent: 4285723 (1981-08-01), Cartwright et al.
patent: 4384135 (1983-05-01), Cartwright et al.
patent: 4388472 (1983-06-01), Cartwright et al.
patent: 4589914 (1986-05-01), Cartwright
patent: 4738711 (1988-04-01), Barton et al.
Czyzewski Jerzy
Hardy Colin
Levin Daniel
Martin Tony R.
Imperial Chemical Industries plc
Kirschner Helene
Willis Prince E.
LandOfFree
Chemical process does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Chemical process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical process will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-854160