反応式
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:9]2[CH2:14][CH2:13][N:12](C)[CH2:11][CH:10]2[C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:6]=[CH:7][CH:8]=1.COC1C=C(C=CC=1)C=O.F[B-](F)(F)F.C[O+](C)C.[BH4-].[Na+]>C(O)C>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:9]2[CH2:14][CH2:13][NH:12][CH2:11][CH:10]2[C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:6]=[CH:7][CH:8]=1参加物
実験手順
In the preparation of ethyl 4-(3'-methoxyphenyl)-1-methylpiperidine-3-carboxylate (23), a synthesis of 4-aryl 2-unsubstituted nipecotic acids was developed. In this process modifying a known procedure [cf. C. F. Koelsch, J. of the Am. Chem. Soc., 65:2459 (1943)], 3-methoxybenzaldehyde (18) was converted to the amide ester, ethyl 4-(3'-methoxyphenyl)-2-piperidone-5-carboxylate (21), via standard procedures. Selective reduction of the amide function of 21 was achieved by reaction with trimethyloxonium fluoroborate followed immediately by treatment with NaBH4 in ethanol to yield amino ester, ethyl 4-(3'-methoxyphenyl)piperidine-3-carboxylate (22). Reductive methylation gave the required nipecotate 23 in 48% overall yield from 3-methoxybenzaldehyde (18).
出典と根拠
- ORDレコード
- ord-1f31d8078a304ae085e9bcac7846089b
- 出典データセット
- uspto-grants-1982_08
- 特許番号
- US04346224
関連ノート
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