5-Phenyl-1,2,3,6-tetrahydro quinolin-6-ones

For the preparation of 4-(1.2.3.4-tetrahydroquinolino)-phenol 17 three different procedures were worked out [Eqs. (6)-(8)]. 17 was prepared by reacting N-p-methoxyphenyl-anthranilic acid with acetic anhydride and subsequent saponification to l-p-methoxyphenyl-4-hydroxy-2-quinolone, reaction withPOCl3 to form l-p-methoxyphenyl-4-chloro-2-quinolone, hydrogenation to l-(p-methoxy-phenyl)-3.4-dihydro-2-quinolone, splitting the ether with HBr to l-(p-hydroxy-phenyl)3.4-dihydro-2-quinolone, and reduction with LiAlH4 [Eq. (6)J. Another synthetic possibility was the reaction of p-anilinophenol with (3-propiolactone and subsequent cyclization to l-(p-acetoxyphenyl)2.3-dihydro-4-quinolone 18. The next step, the Wolff-Kishner reduction, led directly to the desired product [Eq. (7)]. The third way, the direct amination of p-iodoanisole with 1.2.3.4-tetrahydro-quinoline and the subsequent splitting of 4-(1.2.3.4-tetrahydro-quinolino)-anisol with HBr was the best one [Eq. (8)]. Saponification of l-(p-acetoxyphenyl>2.3-... 

Phenyl-l, 2,3,6-tetrahydro[l, 3]thiazino[3,2-n]quinolin-6-ones 90 were prepared in the reactions of 2-mercapto-5-phenyl-l,4-dihydroquinolin-4-ones 103 and 1,3-dihalopropane in 55-79% yields (97JAP(K)97/278780). 

Some other ring expansions involving the intramolecular amino Claisen rearrangement of vinylarylaziridine [ 123], the Diels-Alder reaction of indoles with acetylene derivative [124-127] and the dibromocarbene insertion into quinoline enol ethers [ 128] have been used to prepare 1-benzazepines. On the other hand, treatment of 3-chloro-3-phenyl-l,2,3,4,5,6-hexahydro-l-benz-azocin-2-ones with piperidine causes a ring contraction to give 2-phenyl-2-(l-piperidinylcarbonyl)-2,3,4,5-tetrahydro-l//-l-bcnzazepines in an excellent yield [23]. 

A microwave-assisted three-component coupling reaction of 5-amino-3-phenyl-pyrazole, a cychc 1,3-dicarbonyl compound and an aromatic aldehyde has been described by Chebanov and co-workers [121]. Depending on the apphed reaction conditions a series of 4-aryl-3-phenyl-l,4,6,7,8,9-hexahydro-l// pyrazolo[3,4-h] quinolin-5-ones 80, 9-p-tolyl-6,6-dimethyl-2-phenyl 5,6,7,9-tetrahydro-pyrazolo [5,l-h]quinazolin-8-ones 81, or 4-aryl-5a-hydroxy-4,5,5a,6,7,8-hexahydropyra-zolo[4,3-c]quinolizin-9-ones 82 can be formed (Scheme 61). 

Hydrogenation of ethyl A -[2-(2-pyridyl)ethyl]carbamate in ethanol over Raney Ni at 130°C and 120 atm gave perhydropyrido[l,2-c]pyrimidin-1-one (67YZ663). Cyclization of ethyl Y-[2-(l,2,3,4-tetrahydro-2-quinolyl)ethyl]carbamate at 190-200°C afforded 2,3,4,4a,5,6-hexahydro-l//-pyrimido[l,6-a]quinolin-l-one (60YZ1414), whereas that of l-(2-benzamidoethyl)-6,7-dimethoxy-3,4-dihydroisoquinoline in boiling toluene with phosphoryl chloride led to 4-phenyl-9,10-dimethoxy-6,7-dihydro-2//-pyrimido[6,l-fl]isoquinoline (63YZ1043). 

Ci bHi 7NO3, 1, 2,3,9b-Tetrahydro-9bp-hydroxy- 2/3-methoxy-1a-phenyl-5H-pyrrolO [2,1-a]isoindol-5 One, 46B, 277 ClbHigBrNjO, 1-Methyl-2-phenyl-5,10-dihydro-1H-imidazo[2,1-b]iso-quinolin-4-ium bromide monohydrate, 43B, 366 ClbHigBrN On, 4-Ethoxycarbonyl 5 p-bromooxoben20yl-8,8-dimethyl-3,4,9,1O-tetraazatricyclo[5.3.0.0 ]deca-2,9-diene, 40B, 275 CiBHigBr3N203, 11,12,13-Tribromo-3,6-diethyl-1O-ethoxycarbonyl-3,6-diazatricyclo[7.4.0.0 " ]trideca-2(7),9,11,13-tetraene-8-one, 46B, 277... 

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