4-Substituted-5-phenyl-7-chloro-1, 2-dihydroimidazo [1, 2-α] quinolines (6ae) (substituents at 4-position were a : H, b : CH3, c : C6H5, d : CN, e : N (CH3) 2) and 5-substituted-6-phenyl-8-chloro-2, 3-dihydro-1H-pyrimido [1, 2-α] quinolines (7ae) (substituents at 5-position were in accordance with the (6ae)) were synthesized from 2-amino-5-chlorobenzophenone, and KMnO4 oxidation of the above compounds in acetone were investigated. The oxidation of (6ae) caused dehydrogenation of the imidazo ring to give 4-substituted-5-phenyl-7-chloro-imidazo [1, 2-α] quinolines (8ae) in 3258% yields. On the other hand, the oxidation of (7ac) resulted in the selective oxidation of the methylene group at the 3-position of 2, 3-dihydro-1H-pyrimido ring to carbonyl group, and 5-substituted-6-phenyl-8-chloro-1, 2-dihydro-3H-pyrimido [1, 2-α] quinoline-3-ones (9ac) were obtained in 3858% yields. The oxidations of the derivatives having CN or NMe2 as substituents were difficult to proceed as compared with the cases of other substituted compounds.
Cadalene, the dehydrogenation product of some sesquiterpenes, was synthesized from bromobenzene. The action of methylmagnesium iodide on 3- (p-bromobenzoyl) -propionic acid (1) yielded r- (p-bromophenyl) valerolactone (2). 7-Bromo-4-methyl-1, 2, 3, 4-tetrahydronaphthalene-1-one (4), which was obtained by the reduction and cyclization of (2), was isopropylated and then dehydrogenated to give 6-bromo-1-methyl-4-isopropylnaphthalene (6a). The methylation of Grignard reagent from (6a) with dimethyl sulfate afforded cadalene (7a) along with 1-methyl-4-isopropylnaphthalene (8a) and 5, 5'-dimethyl-8, 8'-diisopropyl-2, 2'-binaphthyl (9a). Similarly, 1, 4, 6-tri- (7b) and 1, 4-dimethylnaphthalene (8b) and 5, 5', 8, 8'-tetramethyl-2, 2'-binaphthyl (9b) were obtained from 6-bromo-1, 4-dimethyl-napht-ha lene (6b).
3, 6-Disubstituted-2-amino-4-phenylquinolines (1) were obtained in 3295% yields by the reaction of 5-substituted-2-aminobenzophenones (substituents of 5-position are H, Cl or CH3) with α-substituted acetonitriles (substituents are H, CH3 or C6H5) in the presence of NaH as a basic catalyst in pyridine. 3-Cyano derivatives in (1) were given in 9598% yields by the reaction of 5-substituted-2-aminobenzophenones with malononitriles in the presence of C2H5ONa in ethanol.