Lithium amide → (3S,alphaR)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-4-pentenoate
反応式
[CH2:1]([NH:4][C@H:5]([CH3:12])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)[CH:2]=[CH2:3].C([Li])CCC.[NH2-].[Li+].[C:20]([O:26][C:27]([CH3:30])([CH3:29])[CH3:28])(=[O:25])[CH:21]=[CH:22][CH:23]=[CH2:24]>O1CCCC1>[CH2:1]([N:4]([C@H:5]([CH3:12])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)[C@H:22]([CH:23]=[CH2:24])[CH2:21][C:20]([O:26][C:27]([CH3:29])([CH3:28])[CH3:30])=[O:25])[CH:2]=[CH2:3]参加物
実験手順
A solution of (R)-N-allyl-α-methylbenzylamine (24) (1.78 g, 11.1 mmol) in anhydrous tetrahydrofuran (20 ml) was cooled to -78° C. and 1.6M butyllithium (6.00 ml, 9.5 mmol) was added dropwise via a syringe. The resulting orange lithium amide solution was stirred at -78° C. for 1 hour. A solution of t-butyl pentadienoate (25) (1.137 g, 7.4 mmol) in anhydrous tetrahydrofuran (15 ml) was then added via a cannula and the solution was stirred for a further 1 hour. The reaction was quenched by the addition of saturated aqueous ammonium chloride solution and the solution was allowed to warm to room temperature. Ethyl acetate (50 ml) was added, followed by brine (10 ml). The organic layer was separated, dried (magnesium sulphate) and filtered and the solvent evaporated under reduced pressure to afford a pale yellow oil. This was purified by flash chromatography on silica gel [ethyl acetate/petroleum ether (1:49)] to afford the title compound (Rf 0.25) as a colourless oil (1.97 g, 85%). δH (300 MHz; CDCl3) 7.40-7.19 (5H, m, Ph), 5.94-5.74 (2H, m, CH2 =CHCH and NCH2CH=CH2), 5.16-5.00 (4H, m, CH2 =CHCH and NCH2CH=CH2), 4.02 (1H, q, J=6.8, PhCHCH3), 3.90 (1H, app. q, J=7.1, NCHCH2), 3.15 (2H, d, J=6.1, NCH2CH=CH2), 2.41 (1H, dd, J=6.4 and 14.5, CH2CO2), 2.31 (1H, dd, J=14.5 and 8.3, CH2CO2), 1.42 (9H, s, (CH3)3C), 1.39 (3H, d, J=6.8, PhCHCH3).
後処理
- customThe reaction was quenched by the addition of saturated aqueous ammonium chloride solution
- additionEthyl acetate (50 ml) was added
- customThe organic layer was separated
- dry with materialdried (magnesium sulphate)
- filtrationfiltered
- customthe solvent evaporated under reduced pressure
- customto afford a pale yellow oil
- customThis was purified by flash chromatography on silica gel [ethyl acetate/petroleum ether (1:49)]
出典と根拠
- ORDレコード
- ord-b5b2668e8c934eaa970d010875a888ec
- 出典データセット
- uspto-grants-2000_03
- 特許番号
- US06037498
反応ノート
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