Tetrahydrofuran → Benzyl 4-(acetyloxy)-3,3-dimethyl-1-oxo-2-oxa-8-azaspiro[4.5]decane-8-carboxylate
反応式
[N:1]1([C:12]([O:14][CH2:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)=[O:13])[CH2:6][CH2:5]C(C(OCC)=O)[CH2:3][CH2:2]1.C[Si]([N-][Si](C)(C)C)(C)C.[Li+].[C:32]([O:35][C:36]([CH3:40])([CH3:39])[CH:37]=[O:38])(=[O:34])[CH3:33].[O:41]1CC[CH2:43][CH2:42]1>>[C:42]([O:38][CH:37]1[C:33]2([CH2:3][CH2:2][N:1]([C:12]([O:14][CH2:15][C:16]3[CH:17]=[CH:18][CH:19]=[CH:20][CH:21]=3)=[O:13])[CH2:6][CH2:5]2)[C:32](=[O:34])[O:35][C:36]1([CH3:40])[CH3:39])(=[O:41])[CH3:43]参加物
反応条件
- 温度
- -78 °C
実験手順
A solution of 1-benzyl 4-ethyl piperidine-1,4-dicarboxylate (2.35 g) was dissolved in tetrahydrofuran (30 mL) and was cooled to −78° C. Lithium bis(trimethylsilyl)amide (9 mL, 1M) was added dropwise under nitrogen and the solution was stirred for 30 min at −20° C. The solution was re-cooled to −78° C. and 1,1-dimethyl-2-oxoethyl acetate (1.17 g) in tetrahydrofuran (5 mL) was added and the mixture was stirred for 30 min. The mixture was quenched (NaHCO3, 30 mL) and the mixture was extracted with ethyl acetate (2×50 mL). The extracts were combined, washed with brine, dried (MgSO4) and were concentrated in vacuo. The crude product was purified by chromatography on silica using 25-75% ethyl acetate in iso-hexane as eluant to afford the product (1.4 g).
後処理
- temperatureThe solution was re-cooled to −78° C.
- stirringthe mixture was stirred for 30 min
- customThe mixture was quenched (NaHCO3, 30 mL)
- extractionthe mixture was extracted with ethyl acetate (2×50 mL)
- washwashed with brine
- dry with materialdried (MgSO4)
- concentrationwere concentrated in vacuo
- customThe crude product was purified by chromatography on silica using 25-75% ethyl acetate in iso-hexane as eluant
出典と根拠
- ORDレコード
- ord-c64c67d4640f4af8913bfca29e5defdd
- 出典データセット
- uspto-grants-2008_07
- 特許番号
- US07393858B2
反応ノート
読み込み中…