三氟乙醛缩半乙醇

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of aniline (2 mL, 21.9 mmol), trifluoroacetaldehyde ethyl hemiacetal (2.6 mL, 21.9 mmol) and p-toluenesulfonic acid monohydrate (220 mg, 1.16 mmol) in ethanol (25 mL) was heated to reflux for 3 h under continuous stirring. The reaction mixture was cooled, the solvent was removed under reduced pressure and the residue was dissolved in EtOAc. The organic layer was washed with a saturated aqueous solution of sodium bicarbonate, dried over anhydrous sodium sulfate and the solvent was removed under reduced pressure to afford title compound 325 (4.16 g, crude) as a yellow oil which was used directly for the next step. to reflux for 3 h under continuous stirring The reaction mixture was cooled the solvent was removed under reduced pressure the residue was dissolved in EtOAc The organic layer was washed with a saturated aqueous solution of sodium bicarbonate dried over anhydrous sodium sulfate the solvent was removed under reduced pressure

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 12 (Scheme 3) (500 mg, 1.47 mmol), trifluoroacetaldehyde ethyl hemiacetal (0.35 mL, 2.94 mmol) and 4-toluenesulfonic acid monohydrate (280 mg, 1.47 mmol) in ethanol (25 mL) was heated to reflux for 48 h. The reaction mixture was concentrated and the residue was purified by column chromatography on silica gel (eluent methanol-dichloromethane 5:95 to 8:92) to afford title compound 318 (470 mg, 1.01 mmol, 68% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm: 8.42 (d, J=5.5 Hz, 1H), 7.85 (d, J=1.2 Hz, 1H), 7.72 (d, J=0.8 Hz, 1H), 7.67 (s, 1H), 7.29 (t, J=9.2 Hz, 1H), 7.08-7.02 (m, 2H), 3.86 (dd, J=9.2, 2.0 Hz, 1H), 6.52 (d, J=5.5 Hz, 1H), 5.68 (qd, J=10.4, 5.2 Hz, 1H), 3.72 (s, 3H), 3.76-3.59 (m, 2H), 1.15 (t, J=7.0 Hz, 3H). LRMS (M+1) 467.0 (100%). was heated to reflux for 48 h The reaction mixture was concentrated the residue was purified by column chromatography on silica gel (eluent methanol-dichloromethane 5:95 to 8:92)

反应条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred solution of 1-nitropentane (1.0 g, 8.5 mmol) and tri-fluoroacetaldehyde ethyl hemiacetal (1.2 mL, 8.5 mL) was added potassium carbonate (K2CO3) (0.06 g, 0.43 mmol). The reaction mixture was heated at 60° C. under Ar for 3 h. The mixture was cooled to R.T., then taken up in EA (50 mL). The organic layer was washed with 1N HCl (2×10 mL), sat. NaCl (2×10 mL), dried (MgSO4), filtered and concentrated to give (2SR)-(3SR)-3-nitro-1,1,1-trifluoro-2-heptanol as a crude oil (1.7 g, 93%): 1H NMR (CDCl3, 300 MHz) δ 0.91 (t, 3H, J=7.2 Hz), 1.24-1.43 (m, 4H), 2.04-2.11 (m, 2H), 4.08-4.77 (m, 3H) ppm. The mixture was cooled to R.T. The organic layer was washed with 1N HCl (2×10 mL), sat. NaCl (2×10 mL) dried (MgSO4) filtered concentrated