6-Methoxy-1,2,3,4-tetrahydroquinoline

General procedure: A 20 mL Schlenk tube was charged with quinoline (1a; 65 mg, 0.5 mmol), Cu(OAc)2 (4.5 mg, 0.025 mmol), B2(OH)4 (135 mg, 1.5 mmol), and MeCN (2.0 mL). The mixture was stirred at 40 °C for 8 h until the reaction was completed (TLC), then cooled to room temperature and concentrated under reduced pressure. Water (10 mL) was added and the mixture was extracted with EtOAc (3 x 10 mL). The organic phases were combined, dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by column chromatography with petroleum ether/ethyl acetate (8:1) as an eluent to give a brown liquid (2a: 65 mg, 98percent yield).6-methoxyquinoline (0.3 mmol, 48 mg), Tetrahydroxy diboron (0.9mmol, 81mg), Cu (OAc) 2 (0.015 mmol, 2.5 mg) was added to 1 mL of acetonitrile, 40 ° C for 12 hours, The residue was purified by thin layer chromatography to give 44.0 mg of 6-methoxytetrahydroquinoline in 90percent yield, 98percent purity, General procedure: In a 10 mL Schlenk tube, Fe(OTf)To the stirred solution of 6-methoxyquinoline 1 (5 g, 31.44 mmol) in ethanol, Ni-Al alloy (2.5 g) was added and stirringwas continued for 30 min. Further, reaction mass was cooled to 0–4 C and then aqueous sodium hydroxide solution (10percent w/v, 50 ml)was added slowly. After the complete addition, reaction mixturewas further stirred at room temperature for 6 h. After completionof reaction as per TLC, reaction mass was passed through a tightcelite bed, further ethanol (2 75 ml) was passed through thecelite bed. Combined filtrate was evaporated on rotary evaporatortill its volume remained one-fourth to its original volume. Further, reaction mass was acidified with 2 N HCl, until its pH became neutral.Further, reaction mass was taken in separating funnel andextracted twice with ethyl acetate (2 150 ml). Combined ethylacetate layer was first washed with water (300 ml) and then withbrine (300 ml). Ethyl acetate layer was dried over anhydroussodium sulphate and finally evaporated on rotary evaporator toafford the compound 2 as crude oil. Crude 2 was purified by columnchromatography using 5percent ethyl acetate in hexane as mobilephase and silica (mesh size 100–200) as stationary phase, whichafforded the pure compound 2, as light yellow oil with 87percent yield[33].The elemental iodine (0.05 mmol) and 6-methoxy-quinoline (0.25 mmol) were added to the reaction flask to displace the air.Dichloromethane (1 mL) and pinacol borane (1 mmol) were added separately;After stirring at room temperature for 24 hours, The reaction mixture was diluted with dichloromethane (5 mL).The combined organic layers were dried over anhydrous sodium sulfate, filtered and evaporated.The crude product was separated by column chromatography (ethyl acetate: petroleum ether 1percent to 10percent).6-methoxy-tetrahydroquinoline, colorless oil, The yield was 85percent.6-Methoxyquinoline (3.0 g, 18.85 mmol) and PtO2 (0.2 g 0.8 mmol) were dissolved in methanol (20 mL) andheated to 45 °C and stirred for 24 hours. The reaction was detected by TLC. After the reaction was cooled to roomtemperature, the residue was isolated by silica gel column chromatography (petroleum ether/ethyl acetate = 10: 1) toobtain a compound 26A (pale yellow oil, 1.2 g, the yield was 39percent) after spin-drying the solvent.1H NMR (400 MHz, CHLOROFORM-d) d 6.51-6.66 (m, 2H), 6.45 (d, J = 8.5 Hz, 1H), 3.73 (s, 3H), 3.20-3.30 (m, 2H), 2.76 (t, J = 6.5 Hz, 2H), 1.86-1.98 (m, 2H).Compound 6-Methoxy-3, 4-dihydroquinolin-2(1H)-one (1.1 g, 6.21 mmol)Add 50 mL of anhydrous THF to the three-necked flask.LiAlH4 (0.7 g, 18.63 mmol) was added in portions under ice-bath conditions.After it is added, it is heated to reflux.Check the progress of the reaction through the TLC point plate, About 2h reaction is completed, Post-processing, Move 0.7g of water dropwise into the ice bath and stir for 15min.Then add 15percent sodium hydroxide solution (0.7g) dropwise and stir for 15min.Then add 2.1g water dropwise and stir for 0.5h.After the addition of anhydrous magnesium sulfate (0.7g) stirring 0.5h, filter, The filter cake is rinsed with THF.The filtrate was dried over anhydrous magnesium sulfate.Concentrated to an oil (0.92 g, yield 91.1percent)

Molecular Weight:163.22
XLogP3:2.3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:1
Exact Mass:163.099714038
Monoisotopic Mass:163.099714038
Topological Polar Surface Area:21.3
Heavy Atom Count:12
Complexity:149
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes