Industrial process for preparation of 1,2-dihydroquinoline derivative or a salt thereof, and intermediate for preparation thereof

A compound represented by formula (2) or a salt thereof:

• wherein R2 represents an arylalkyl group, an arylalkyloxyalkyl group, or a substituted silyl group, and R1 represents a hydrogen atom or the same group as R2.

A compound represented by formula (3) or a salt thereof:

• wherein R2 represents an arylalkyl group, an arylalkyloxyalkyl group, or a substituted silyl group, and R1 represents a hydrogen atom or the same group as R2.

A compound represented by formula (4) or a salt thereof:

• wherein R2 represents an arylalkyl group, an arylalkyloxyalkyl group, or a substituted silyl group, and R1 represents a hydrogen atom or the same group as R2.

A compound represented by formula (5) or a salt thereof:

• wherein R2 represents an arylalkyl group, an arylalkyloxyalkyl group, or a substituted silyl group, and R1 represents a hydrogen atom or the same group as R2.

A compound or a salt thereof, the compound selected from the group consisting of 8-(4-methoxybenzyloxy)-2,2,4-trimethyl-1,2-dihydro-6-oxa-1-azachrysen-5-one, 6-[2-hydroxy-4-(4-methoxybenzyloxy)phenyl]-5-hydroxymethyl-1,2-dihydro-2,2,4-trimethylquinoline, 5-hydroxymethyl-6-[2-methoxy-4-(4-methoxybenzyloxy)phenyl]-1,2-dihydro-2,2,4-trimethylquinoline, [5-[(5-fluoro-2-methylphenoxy)methyl]-6-[(2-methoxy-4-(4-methoxybenzyloxy)phenyl)]-1,2-dihydro-2,2,4-trimethyl quinoline, and [5-[(5-fluoro-2-methylphenoxy)methyl]-6-(4-hydroxy-2-methoxyphenyl)-1,2-dihydro-2,2,4-trimethylquinoline.