6-CHLORO-2,3-DIHYDRO-1H-INDOLE

Reduction of Indoles to Indolines:; PREPARATION 142; 6-Chloro-2, 3-dihydro-lH-indole; Dissolve 6-chloro-lH-indole (2 g, 0.013 mol) in acetic acid (10 mL) under nitrogen. Add sodium cyanoborohydride (1.24 g, 1.5 eq) and stir 20 minutes at room temperature. Dilute with ethyl acetate and extract with sodium hydroxide (5 N aqueous). Dry over magnesium sulfate, filter and concentrate to give 2.35 g (116percent) crude product. MS (ES, m/z) : 154.0 (M+1).6-chloro-2, 3-dihydro-1H-indole Synthesis of In acetic acid (2.0 mL) solution of 6-chloro -1H- indole (200 mg, 1.3 mmol), sodium cyanoborohydride (170 mg, 2.6 mmol) was added at room temperature, and was stirred at 3 hours. It added 1 N aqueous sodium hydroxide to the reaction mixture (30 mL) at room temperature, followed by extraction with ethyl acetate (30 mL). The organic layer was dried over sodium sulfate, and concentratedIt was. The resulting concentrate was purified by silica gel column chromatography is purified by (eluent ethyl acetate / n-hexane = 25/75), 6-chloro-indoline as a colorless oilObtained (180mg, 87percent yield).Preparation 30: 6-Chloro-2, 3-dihydro-1 H-indole6-Chloroindole (1.0 g, 6.6 mmol) was dissolved in a solution of borane in THF (1 M, 9.83 mmol) at 0 °C and stirred for 30 min. TFA (9.83 mL) was added dropwise and the solution stirred at 0 °C for 30 min. 6 M aqueous NaOH was added until the solution was basic (pH 1 1 ). The aqueous solution was extracted with DCM (3 x 25 mL), dried over sodium sulfate, filtered and concentrated to give the title compound (864 mg, 86percent) as a yellow oil. In a 250 mL round bottom flask, 12.4 grams of sodium cyanoborohydride (198 mmol, 2 eq. ) were added potion-wise over 5 minutes to a solution of 15 grams (98.9 mmol) of 6-chloroindole. After stirring for 22 hours, the mixture had become a brown solution and analysis by [HPLC] (MRH 1 method) revealed no starting material remaining and a mixture of two product peaks. The mixture was diluted with 100 [ML] of water, then made basic [WITH-200] mL of 6N sodium hydroxide. The desired product was extracted into 3 X 400 mL of methylene chloride. The extracts were then dried over anhydrous magnesium sulfate and evaporated in vacuo leaving a cloudy oil. The crude product was chromatographed over a plug of silica in 100 percent methylene chloride giving a mixed fraction [(RF=] 0.9 and 0.7), a pure product fraction [(RF= 0. 7), ] and a baseline fraction (Rf = 0.0-0. 2). The pure fraction was evaporated to dryness in vacuo to yield a clear, colorless oil weighing 10.90 grams (72 percent). It was stored at [4°C] and saved for future [USE. 1H] NMR (300 MHz, DMSO-d6) 8 6.95 (d, J= 5 Hz, 1 H), 6.46 (d, [J=] 5 Hz, 2 H), 3.43 (t, [J=] 6, 2 H), 2.86 (t, [J=] 6, 2 H).

Molecular Weight:153.61
XLogP3:2.7
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:1
Exact Mass:153.0345270
Monoisotopic Mass:153.0345270
Topological Polar Surface Area:12
Heavy Atom Count:10
Complexity:126
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes