C - Chemistry – Metallurgy – 07 – D
Patent
C - Chemistry, Metallurgy
07
D
260/356.1, 260/2
C07D 311/46 (2006.01) C07D 311/56 (2006.01) C07D 405/02 (2006.01) C07D 407/02 (2006.01)
Patent
CA 1263396
ABSTRACT PROCESS FOR PREPARING 4-HYDROXYCOUMARIN DERIVATIVES The invention provides a process for preparing a 4-hydroxycoumarin derivative having anti-coagulant properties, useful as a rodenticide, of formula Image (I) wherein R1 and R2 are independently selected from the group consisting of hydrogen, halogen, alkyl of up to 6 carbon atoms and alkoxy of up to 6 carbon atoms, and R3 represents a group selected from (a) Image where X represents a halogen atom or a group C1-12 alkyl, C1-12 alkoxy, C3-8 cycloalkyl, CN, SO2R5, CF3, OCF3, COOR5 or COR5, where R5 is C1-6 alkyl, n' is 0, 1 or 2 and Y is a fluorine or chlorine atom; Image (b) where n' and Y are as defined above, X is as defined above or is hydrogen, n" is O or 1 and D is an oxygen atom or a group -O-(CH2)m-, -(CH2)m-O-, -O-(CH2)m-O-, -(CH2)m-O-(CH2)p-, -(CH2)-m, or -CH=CH-, or a sulphur analogue thereof, wherein m is in the range 1 to 6 and p is in the range 1 to 6; (c) Image where X, n' and Y are as defined in (a) above: (d) a group selected from Image and Image ; and (e) a group selected from Image where X and n" are as defined in (b) above, A is an oxygen or sulphur atom and D' is an oxygen atom or a -CH2- grcup, which process comprises condensing 4-hydroxycoumarin with a compound of formula (VI) Image or the corresponding 1,2-dihydronaphthalene, wherein R1, R2 and R3 are as defined above, and L is a hydroxy group or a halogen atom, in the presence of an organic solvent and a catalyst characterised in that the solvent is selected from formic acid, a mixture of formic acid and at least one C2-6 aliphatic acid having a boiling temperature at atmospheric pressure in the range 60°C to 105°C and a liquid halogenated hydrocarbon having a boiling temperature of at least 60°C, and reaction is effected at a temperature in the range 60°C to the reflux temperature of the reaction mixture.
490120
Boehm Peter
Entwistle Ian David
Shell Canada Limited
Smart & Biggar
LandOfFree
Process for preparing 3-(1,2,3,4-tetrahydro-1-... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for preparing 3-(1,2,3,4-tetrahydro-1-..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for preparing 3-(1,2,3,4-tetrahydro-1-... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1264229