Synthesis of 3,4-dihydroisoquinolines, 2-alkyl(Acyl)-1(2H)-3,4-dihydroisoquinolinones, 2-alkyl-1(2H)-isoquinolinones and 1-alkyl-2(2H)-quinolinones by oxidation with potassium permanganate

Venkov, Atanas P.; Statkova-Abeghe, Stela

doi:10.1016/0040-4020(95)00971-x

Cited by 44 publications

(13 citation statements)

References 30 publications

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“…Consecutive reduction of the formed vinylogous urethane 12 and TIPS protection gave 13 (Scheme 2). Compound 13 was then oxidised with KMnO 4 at À7 8C [14] to give the imine 15 with an overall yield of 55 % (6 steps from the starting materials 3 and 10). Transfer hydrogenation with triethylammonium formate in the presence of the chiral Ru catalyst (R,R)-16 developed by Noyori [15] provided the tetrahydroisoquinoline (1S)-14 in a yield of 93 % and 95 % ee.…”

Section: Resultsmentioning

confidence: 99%

Enantioselective Total Syntheses of the Ipecacuanha Alkaloid Emetine, the Alangium Alkaloid Tubulosine and a Novel Benzoquinolizidine Alkaloid by Using a Domino Process

Tietze

Rackelmann

Müller

2004

Chemistry A European J

111

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The first enantioselective syntheses of the Ipecacuanha alkaloid emetine (1) and the Alangium alkaloid tubulosine (2) is described employing a domino Knoevenagel/hetero-Diels-Alder reaction and an enantioselective catalytic transfer hydrogenation of imines as key steps. Thus, hydrogenation of the imine 15 with the catalyst (R,R)-16 gives the tetrahydroisoquinoline 14 with 95 % ee which was transformed into the aldehyde (1S)-7. The three-component domino reaction of (1S)-7 with 6 and 8 led to 19, which in a second domino process was treated with K(2)CO(3) in methanol followed by a hydrogenation to give the benzoquinolizidine 4 together with the diastereomers 22 and 23 in a overall yield of 66 %. Further transformation of 4 with the amines 3 and 5 yielded enantiopure emetine (1) and tubulosine (2), respectively. In addition, starting from 19 the novel benzoquinolizidine alkaloid 34 was synthesised; this compound resembles the vallesiachotamine alkaloid dihydroantirhin 31, which has not been isolated so far but probably must also exist in nature.

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Section: Resultsmentioning

confidence: 99%

Enantioselective Total Syntheses of the Ipecacuanha Alkaloid Emetine, the Alangium Alkaloid Tubulosine and a Novel Benzoquinolizidine Alkaloid by Using a Domino Process

Tietze

Rackelmann

Müller

2004

Chemistry A European J

111

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“…1 H NMR spectra were recorded at 400 MHz and 13 C NMR spectra were recorded at 100 MHz in dimethylsulfoxide (DMSO-d 6 ) or CDCl 3 using a 300-or 400-MHz spectrometer. Chemical shifts are reported in d (ppm) relative to tetramethylsilane (TMS).…”

Section: Methodsmentioning

confidence: 99%

“…The available methods for the construction of isoquinoline ring include the Pomeranz-Fritsch reaction, [4] Bischler-Napieralski reaction, [5] and Pictet-Splengler reaction. [6] Homophthalaldehyde, which can readily be obtained by the ozonolysis of indene, can be cyclized with ammonia to form the isoquinoline derivative in good yields. [7] Palladium-catalyzed reaction of o-bromoarylaldehyde with an alkyne and subsequent reaction with ammonia can also produce the isoquinoline derivative.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Isoquinoline Derivatives from β-Hydroxyarylethanamides

Suresh

Muthusubramanian

2015

Synthetic Communications

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A simple and efficient protocol for the construction of medicinally important substituted isoquinolines through intramolecular cyclization of b-hydroxyarylethanamides using acetic anhydride and phosphorous pentoxide in dioxane has been described. The chemo-and regioselectivities due to the influence of different catalysts were investigated and optimized for good to excellent yields. All the synthesized compounds have been characterized by NMR and mass spectral analyses.

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“…Treatment of the 1-isopropyl-2-methylisoquinolinium iodide (1a) with acid (method A) gave compounds 5a, 6a [5], 7a [5,6], and 2-methylisoquinolin-1(2H)-one (8) [8]. Under the same conditions the salt 1b gave compounds 5b, 6b, 7b and 8 (for Scheme see page 77).…”

mentioning

confidence: 97%

“…Salt 1b gave the amino alcohol 4b, 1'H-spiro(cyclohexane-1,2'-naphthalin)-1'-on-3'-ol (6b), 1'H-spiro(cyclohexane-1,2'-napthaline)-1',3'-diol (9b), and 2-methylisoquinolin-1(2H)-one (8). 1 H and 13 C NMR spectra were recorded on a Bruker Avance-400 spectrometer (400 and 100 MHz respectively) using CDCl 3 at 23ºC with TMS as internal standard.…”

mentioning

confidence: 99%

Novel nucleophilic rearrangement of 1-substituted isoquinolines using an alcoholic sodium hydroxide solution

Теренин

Волков

Иванов

et al. 2011

Chem Heterocycl Comp

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The reactions of 1-substituted isoquinolinium salts have been studied in the cases of the 1-isopropyl-2-methyl-and 2-methyl-1-cyclohexylisoquinolinium iodides using an alcoholic solution of sodium hydroxide. The possibility of preparing a wide range of spirocyclic ketones, alcohols, amino alcohols, and isochroman-3-ones has been demonstrated.It has previously been shown in our laboratory that rearrangement of quaternary isoquinolinium salts with a methine group at position 1 occurs with an alcoholic alkylamine solution [1]. This recyclization gave a low yield of -amino--tetralones since the principal route for the reaction is an N-desalkylation to give the starting isoquinoline. It might be expected that exchange of the N-nucleophile for an O-nucleophile would lead to a lower yield of side reaction products.The 1-isopropyl-2-methyl-(1a) and 1-cyclohexyl-2-methyl-isoquinolinium (1b) iodides were prepared by quaternization of the corresponding isoquinolines by methyl iodide, sealed in an ampoule with an alcoholic solution of sodium hydroxide, and heated for 18-20 h at 150ºC. Analysis of the reaction mixtures by NMR spectroscopy showed that the reaction results in a mixture of complex composition. In the initial separation of the reaction products it was extracted with an acid medium and then with base.In the case of the 1-isopropyl-2-methylisoquinolinium iodide (1a), extraction of the reaction mixture at pH below 7 gave the 2,2-dimethyl-1,2-dihydronaphthalin-1-ol (2a) [2][3][4] and the 1-isopropyl-1,4-dihydro-(3H)isochroman-3-one (3a) [4]. Extraction from the basic medium gave the 2,2-dimethyl-3-methylamino-1,2,3,4-tetrahydronaphthalin-1-ol (4a). When a cyclohexyl substituent was present at position 1 of the starting salt 1b there were obtained the compounds with a spirocyclic structure 2b, 4b and an isochromanone with a cyclohexyl group at position 1 (compound 3b).With a shorter heating time (8 h) the amino alcohols 4a,b were not observed and there were separated from the basic medium the 2,2-dimethyl-3-methylamino-3,4-dihydronaphthalin-1(2H)-one (5a) and the 3'-(methylamino)-3',4'-dihydro-1'H-spiro(cyclohexane-1,2'-naphthalin)-1'-one (5b), previously reported as the reaction products of salts 1a,b with an alcoholic methylamine solution [1].

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Synthesis of 3,4-dihydroisoquinolines, 2-alkyl(Acyl)-1(2H)-3,4-dihydroisoquinolinones, 2-alkyl-1(2H)-isoquinolinones and 1-alkyl-2(2H)-quinolinones by oxidation with potassium permanganate

Cited by 44 publications

References 30 publications

Enantioselective Total Syntheses of the Ipecacuanha Alkaloid Emetine, the Alangium Alkaloid Tubulosine and a Novel Benzoquinolizidine Alkaloid by Using a Domino Process

Enantioselective Total Syntheses of the Ipecacuanha Alkaloid Emetine, the Alangium Alkaloid Tubulosine and a Novel Benzoquinolizidine Alkaloid by Using a Domino Process

Synthesis of Isoquinoline Derivatives from β-Hydroxyarylethanamides

Novel nucleophilic rearrangement of 1-substituted isoquinolines using an alcoholic sodium hydroxide solution

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