Processes for preparing quinoline derivatives and intermediates thereof

A production method of a quinoline derivative of the formula (V)

• wherein R1, R2, R3, R4, R5 and R6 each independently represent a hydrogen atom, a halogen atom, a trifluoromethyl group, a trifluoromethoxy group, an optionally protected hydroxyl group, an alkyl group optionally having substituents, a cycloalkyl group optionally having substituents, an aryl group optionally having substituents, an aralkyl group optionally having substituents, an alkoxyl group optionally having substituents or an aryloxy group optionally having substituents, which comprises:
• reacting a quinolinecarbaldehyde of the formula (I)
• wherein R1, R2, R3, R4, R5 and R6 are as defined above,
• with any of the following compounds (a) to (c) in the presence of a base,
• (a) a phosphonium salt compound of the formula (II)
• wherein R7 and R8 each independently represent a hydrogen atom, an alkyl group optionally having substituents, an acyl group optionally having substituents or an aralkyl group optionally having substituents, or in combination represent an alkylene group, an arylene group or an aralkylene group, R9 represents an alkyl group optionally having substituents or an aryl group optionally having substituents, and X represents a halogen atom,
• (b) a phosphonate compound of the formula (III)
• wherein R7, R8 and R9 are as defined above, and
• (c) a phosphonate compound of the formula (IV)
• wherein each R9 is as defined above, and R10 and R11 each independently represent a hydrogen atom, an alkyl group optionally having substituents, a cycloalkyl group optionally having substituents, an aryl group optionally having substituents or an aralkyl group optionally having substituents, or in combination represent an alkylene group, an arylene group or an aralkylene group,
• and then hydrolyzing the resulting compound.