Patent GB-1391834-A (GB)
Title: Substituted benzimidazole carbamates and tautomers thereof
IPC: C07D235/32
Filed: 1972-05-01
Abstract: 1391834 Substituted benzimidazole carbamates SCHERING AG 1 May 1972 [5 May 1971] 20114/72 Heading C2C Novel compounds of general Formula (I) in which R 1  and R 2  (which may be the same or different), each represents an aromatic, aliphatic or cycloaliphatic hydrocarbon group which may be mono-, di- or poly-substituted and R 1  may also represent a hydrogen atom, R 3  represents an aliphatic hydrocarbon group, R 4  represents a hydrogen atom, an alkyl, halogenoalkyl or alkoxy group, a halogen atom or a nitro group and R 5  represents a hydrogen atom or a -COON = CR<SP>1</SP> 1 R<SP>1</SP> 2 , -CONHR<SP>11</SP> 2 , or -COOR<SP>1</SP> 3  group, in which R<SP>1</SP> 1  and R<SP>1</SP> 2  (which may be the same or different), each represents an aromatic, aliphatic or cycloaliphatic hydrocarbon group which may be mono-, di- or poly-substituted and R<SP>1</SP> 1  may also represent a hydrogen atom, R<SP>11</SP> 2  represents an aromatic, aliphatic or cycloaliphatic hydrocarbon group which may be mono-,di- or poly-substituted and R<SP>1</SP> 3  represents an aliphatic hydrocarbon group, and tautomeric forms of the compounds of Formula I when R 5  represents a hydrogen atom may be prepared by one of the following methods: (i) when R 5 =H or -COON=CR1 1 R1 2 , a compound of Formula (II) is reacted in the presence of a diluent and an acid binding agent with one or two stoichiometric portions of a chloroformyloxime of Formula (III) Cl-CO-O-N = CR 1 R 2 ; (ii) when R 5  represents a -CO-NH-R<SP>11</SP> 2  or -COOR<SP>1</SP> 3  group, a compound of Formula II is reacted in the presence of a diluent and an acid binding agent with a chloroformyloxime of Formula III to form a compound of Formula I where R 5  = H which is then reacted with (a) a chloroformic acid ester of formula to form a compound of Formula I in which R 5  represents a -COOR<SP>1</SP> 3  group, or (b) a carbamic acid chloride of formula to form a compound of Formula I in which R 5  represents a -CO-NH-R<SP>11</SP> 2  group; or (c) an isocyanate of formula OCN-R11 2  to form a compound of general Formula I in which R 5  represents a -CO-NH-R11 2  group; or (iii) when R 5  represents H or -CONHR<SP>11</SP> 2  or -COOR<SP>1</SP> 3 , a compound of Formula II is reacted with phosgene and the resulting chloroformyl benzimidazole of formula is reacted with an oxime of formula or with an alkali metal salt thereof, and if desired the resulting compound of general Formula I is reacted as in (ii)(a), (b) or (c) above; or (iv) a compound of general Formula IV is reacted in the presence of diluent and acid binding agent with a chloroformyloxime of Formula III to form a compound of general Formula V which is then reacted with a chloroformic acid ester of formula Cl-CO.OR 3  to form a compound of general Formula I wherein R 5  = H, which may then be reacted with a compound of formula Cl-CO-O-N=CR<SP>1</SP> 1 R<SP>1</SP> 2  or Cl-CO- OR<SP>1</SP> 3 or Cl-CO-NH-R<SP>11</SP> 2 orOCN-R<SP>11</SP> 2 to form the appropriate compound of general Formula I. The novel compounds exhibit fungicidal properties.