Diisopropylethylamine → HCID 58284927, compound

Participants

Reaction Steps

Platinum on carbon (5%, 30 mg) was added to a solution of the product of Example 26B (0.67 g, 1.88 mmol) in methanol (100 mL). The reaction flask was evacuated and purged with nitrogen (5 cycles) and then with hydrogen (5 cycles), and the suspension was stirred under hydrogen (1 atm) for 18 hours. The reaction flask was evacuated and purged with nitrogen (5 cycles), and the mixture was filtered through diatomaceous earth with ethyl acetate (50 mL) and methanol (50 mL) rinses. The filtrate was concentrated under vacuum and the residue was dissolved in N,N-dimethylformamide (8 mL). O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (720 mg, 1.89 mmol) and diisopropylethylamine (0.395 mL, 2.262 mmol) were added, and the solution was stirred at room temperature for 3 hours. The mixture was diluted with water (50 mL) and extracted with ethyl acetate (2×50 mL). The combined extracts were washed successively with 1 N NaOH (50 mL) and brine (40 mL), and then concentrated under vacuum. The residue was purified by flash chromatography (SiO2 eluted with CH2Cl2—CH3OH, 100:0-95:5) to provide the title compound: 1H NMR (300 MHz, CD3OD) δ ppm 1.98 (dd, J=13.4, 1.2 Hz, 1H), 2.27 (dt, J=11.4, 3.1 Hz, 1H), 2.40 (t, J=10.9 Hz, 1H), 2.67 (dd, J=13.2, 7.5 Hz, 1H), 2.82-2.89 (m, 1H), 2.89-2.97 (m, 1H), 3.01-3.09 (m, 1H), 3.22 (dd, J=11.5, 2.7 Hz, 1H), 3.35-3.44 (m, 1H), 3.61 (s, 2H), 6.98 (dd, J=8.1, 1.7 Hz, 1H), 7.03 (td, J=7.3, 1.7 Hz, 1H), 7.10-7.22 (m, 2H), 7.25-7.39 (m, 5H); MS (DCI) m/z 308 (M+H)+.

Provenance & Evidence