Lithium borohydride → 4-[1-(4-Benzyloxy-5-methoxy-2-nitro-phenyl)-2-hydroxy-ethylamino]-benzonitrile

関与物質

反応手順

4-{2-propanesulfonylamino-1-[4-(2-chloro-1-phenyl-ethoxy)-3-methoxy-phenyl]-ethylamino}-benzamidine was prepared similarly to Example 2, except propanesulfonyl chloride was substituted for benzenesulfonyl chloride in the reaction with 4-{2-amino-1-[4-(2-chloro-1-phenyl-ethoxy)-3-methoxy-phenyl]-ethylamino}-benzonitrile. MS(M+H)=545. 4-Benzyloxy-5-methoxy-2-nitrobenzaldehyde (12.2 g 42 mmoles) and 4-aminobenzonitrile (5 g, 42 mmoles) were dissolved in methanol (165 ml) and stirred for two hours and then heated to 60° C. for 30 minutes. The reaction was allowed to cool to room temperature and benzyl isonitrile (5 g. 42 mmoles) added. The reaction was cooled to 0° C. and boron trifluoroetherate (16 ml, 126 mmoles) added dropwise over five minutes. The reaction was stirred at 0° C. for 20 minutes and then allowed to come to room temperature and then stirred at ambient temperature for two hours. Water (4 ml) was added and the mixture stirred at room temperature overnight. A yellow precipitate was evident the next morning and the solid filtered off. The solid was washed with methanol and air dried to yield 8 grams of the desired product. The solvent from the filtrate was removed in vacuo and replaced with ethyl acetate. The solution was washed with water and saturated sodium bicarbonate, dried over anhydrous magnesium sulfate and the solvent removed. The crude material was submitted to flash chromatography (hexanes: ethyl acetate, 1:1) to yield an additional 7 g of the desired product (4-Benzyloxy-5-methoxy-2-nitro-phenyl)-(4-cyano-phenylamino)-acetic acid methyl ester. 1HNMR(CDCl3): 7.68 (s, 1H), 7.4 (m, 7H), 7.0 (s, 1H), 6.61 (d, 2H), 6.2 (s, 1H), 5.2 (s,2H), 3.87 (s, 3H), 3.75 (s, 3H). (4-Benzyloxy-5-methoxy-2-nitro-phenyl)-(4-cyano-phenylamino)-acetic acid methyl ester (4.5 g, 10 mmole) was dissolved in dimethoxyethane and lithium borohydride (0.210 g, 10 mmole) added. The reaction was heated to reflux for three hours and cooled to room temperature. The reaction was quenched with water containing acetic acid and diluted with ethyl acetate. After transferring to a separatory funnel, the organic layer was washed with water several times. The organic layer was dried over anhydrous sodium sulfate, filtered and the solvent removed. The crude material was then submitted to flash chromatography to yield 3.1 g of 4-[1-(4-Benzyloxy-5-methoxy-2-nitro-phenyl)-2-hydroxy-ethylamino]-benzonitrile (74%).

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