Diethyl Ether → (+/-)-benzyl (1S,2S)-2-hydroxy-2-methylcyclohexylcarbamate

反応式

[O:1]=[C:2]1[CH2:7][CH2:6][CH2:5][CH2:4][CH:3]1[NH:8][C:9](=[O:18])[O:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.C[Mg+].[Br-].[CH3:22]COCC>C1COCC1>[OH:1][C@@:2]1([CH3:22])[CH2:7][CH2:6][CH2:5][CH2:4][C@@H:3]1[NH:8][C:9](=[O:18])[O:10][CH2:11][C:12]1[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=1

参加物

実験手順

Benzyl 2-oxocyclohexylcarbamate (173 mg, 0.7 mmol) in THF (3 mL) was cooled to −78° C. and added MeMgBr in ether (0.7 mL, 2.1 mmol) dropwise via syringe. The ice bath was removed and the reaction was allowed to stir at rt for 3 h. The reaction was quenched with sat. aqueous NH4Cl (1 mL) and partitioned between ethyl acetate and water. The layers were separated and the organic layer washed with brine, dried (Na2SO4), filtered and concentrated. The product was subjected to flash chromatography on silica gel (10% to 70% ethyl acetate/hexanes) to afford the title compound (81 mg, 88% yield) as a single diastereomer. This material was used as is in the next transformation.