Triethylamine → HCID 68439254, compound

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Reaction Steps

To 58C (15 mmol) in CH2Cl2 (100 mL) at −15° C. was added Et3N (2.1 mL, 15 mmol) followed by TiCl4 (1.0 M in CH2Cl2, 30 mL, 30 mmol). The mixture was stirred from −15° C. to rt over 3.0 h before it was quenched with sat. K2CO3 (100 mL) at 0° C. and stirred at rt for 1.0 h. The mixture was filtered through a pad of wet Celite®, extracted with CH2Cl2 (3×40 mL). The organic layer was washed with water, dried over Na2SO4. A small portion of the dried organic layer was concentrated to give crude ethyl 2-(2-(cyclopropylthio)phenyl)pyrrolidine-3-carboxylate: 1H NMR indicated a mixture of cis and trans isomer in ca. 1:1 ratio. LC-MS 292 (M+H). To the above ethyl 2-(2-(cyclopropylthio)phenyl)pyrrolidine-3-carboxylate in CH2Cl2 was added Et3N (2.1 mL, 15 mmol) and di-tert-butyl dicarbonate (1.0 M in THF, 15 mL, 15 mmol). The mixture was stirred at rt over night before it was quenched with 0.5 N HCl (50 mL). The organic layer was washed with brine, dried (Na2SO4), filtered and concentrated. The resulting residue was purified via silica gel chromatography (0-30% ethyl acetate/hexanes) to provide 58D (3.3 g, 56%) as an oil. 1H NMR indicated a mixture of cis and trans isomer in 1:1 ratio. 1H NMR (400 MHz, CDCl3) δ ppm 0.66-0.75 (m, 2H) 0.87 (t, J=7.03 Hz, 3 H) 1.05-1.08 (m, 2H) 1.14-1.16 (s, 9H) 2.02-2.18 (m, 3H) 3.43-4.19 (m, 5H) 7.06-7.13 (m, 2H) 7.16-7.25 (m, 1H) 7.51-7.60 (m, 1H); LC-MS 292 (M+H).

Provenance & Evidence