Synthesis of tetrahydroquinoline derivative

Catalytic asymmetric aza-Diels-Alder reactions using a chiral lanthanide Lewis acid. Enantioselective synthesis of tetrahydroquinoline derivatives using a catalytic amount of a chiral source [98]... 

Scheme 7.19. Indium-mediated domino reaction for the synthesis of tetrahydroquinoline derivatives...

Savitha G, Perumal PT (2006) An efficient one-pot synthesis of tetrahydroquinoline derivatives via an aza Diels-Alder reaction mediated by CAN in an aqueous medium and oxidation to heteroaryl quinolines. Tetrahedron Lett 47 3589-3593... 

Di Salvo A, Spanedda MV, Ourevitch M, Crousse B, Bonnet-Delpon D (2003) Uncatalyzed domino reaction in hexafluoroisopropanol a simple protocol for the synthesis of tetrahydroquinoline derivatives. Synthesis 14 2231-2235... 

Partially hydrogenated quinoline cores are also present in some important bioactive compounds. For example, the 4-aza-analogs of Podophyllotoxin, a plant lignan that inhibits microtubule assembly, revealed to be more potent and less toxic anticancer agents. In 2006, Ji s group reported a green multicomponent approach to a new series of these derivatives, consisting of the reaction of either tetronic acid or 1,3-indanedione with various aldehydes and substituted anilines in water under microwave irradiation conditions (Scheme 26) [107]. For this efficient and eco-friendly transformation, the authors proposed a mechanism quite similar to the one that was postulated for the synthesis of tetrahydroquinolines in the precedent section. 

Many synthetic methods have been developed for the preparation of quinolines and 1,2,3,4-tetrahydroquinolines due to the interesting biological properties of quinoline-type alkaloids. Most of the synthetic methods are based on the elaboration of aniline derivatives and, as for the synthesis of tetrahydroquinolines, reduction of the corresponding quinolines is the main approach. Only a few methods have been reported for the construction of the quinoline skeleton by N-C(8a) bond formation as the key step, such as oxidative cyclization of 2-(3-aminopropyl)benzene-1,4-diol 89 with K2[Fe(CN)e] (Scheme 42)... 

FIGURE 11.68 Library of tetrahydroquinoline-derived natural product-like derivatives. (From Couve-Bonnaire, S. et al., A solid-phase library synthesis of natural product-like derivatives from an enantiomerically pure tetrahydroquinoline scaffold, J. Am. Chem. Soc., 6, 73, 2004.)... 

By combining regioselective Au(l)-catalyzed enamine synthesis with enantiose-lective transfer hydrogenation, the asymmetric synthesis of tetrahydroquinolines from simple 2-(2-propynyl)aniline derivatives has been achieved (Scheme 15.94). Here, a chiral Bronsted acid is used in combination with the Hantzsch ester to install the chiral center with up to 99% ee [316]. 

A synthesis for the enantiomerically pure 535 was developed starting with D-phenylalanine which upon reaction with methyl chloroformate gave 528 whose reaction with methoxylamine afforded 529. Cyclization with bis(trifluoroacetoxy)iodobenzene in presence of trifluoroacetic acid gave the tetrahydroquinoline derivative 530 which was demethoxylated to give 531. Treatment of 531 with either benzyl chloroformate or... 

Hetero-Diels-Alder reactions have been succesfully employed for the synthesis of arenoquinolizine systems. For example, as shown in Equation 10, treatment of tetrahydroquinoline 319 with Danishefsky s diene 320 in the presence of a Lewis acid gave the benzo[c]quinolizidine derivative 321 <2000JME3718>. 

As shown in Scheme 5.23, 1,2,3,4-tetrahydroquinoline derivatives were synthesized using 3-(2-aminophenyl)propanols as starhng materials and catalyzed by the I/K2CO3 system. This catalytic system was also applicable to the synthesis of 2,3,4,5-tetrahydro-l-benzazepine from 4-(2-aminophenyl)butanol. 

Zhang W, Guo YP, Liu ZG, Jin XL, Yang L, Liu ZL (2005) Photochemically catalyzed Diels-Alder reaction of arylimines with N-vinylpyrrohdinone and N-vinylcarbazole by 2,4,6-triphenylpyrylium salt synthesis of 4-heterocycle-substituted tetrahydroquinoline derivatives. Tetrahedron 61 1325-1333... 

Bismuth(III) Bromide-Catalyzed Synthesis of Substituted Tetrahydroquinoline Derivatives... 

Scheme 5 Bismuth(III) bromide-catalyzed synthesis of substituted tetrahydroquinoline derivatives...

Zhang J, Li C-J (2002) InCl3-catalyzed domino reaction of aromatic amines with cyclic enol ethers in water a highly efficient synthesis of new L2,3,4-tetrahydroquinoline derivatives. J Org Chem 67 3969-3971... 

Sridharan V, Avendano C, Menendez JC (2008) New findings on the cerium(IV) ammonium nitrate catalyzed Povarov reaction stereoselective synthesis of 4-alkoxy-2-aryl-l,2,3,4-tetrahydroquinoline derivatives. Synthesis 1039-1044... 

Rogers JL, Emat JJ, Yung H, Mohan RS (2009) Environmentally friendly organic synthesis using bismuth compounds Bismuth(III) bromide catalyzed synthesis of substituted tetrahydroquinoline derivatives. Catal Commun 10 625-626... 

Fig. 31 Synthesis of enantiopure sugar-derived tetrahydroquinoline derivatives...

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