Hydrochloric Acid → (rac.)-(1R*,5S*)-3-Acetyl-7-{6-[2-(2,6-dichloro-4-methyl-phenoxy)-ethoxy]-pyridin-3-yl}-3,9-diaza-bicyclo[3.3.1]non-6-ene-6,9-dicarboxylic Acid 6-ethyl Ester 9-(2,2,2-trichloro-1,1-dimethyl-ethyl) Ester

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Reaction Conditions

Reaction Steps

HCl (4M in dioxane, 30 mL) was added to a sol. of compound C5 (3.34 g, 4.20 mmol) in CH2Cl2 (30 mL) at 0° C. The mixture was stirred for 1 h at 0° C., then for 1 h at rt. The solvents were removed under reduced pressure, and the residue was dried under high vacuum. The residue was dissolved in CH2Cl2 (30 mL), and DIPEA (2.88 mL, 16.8 mmol) was added. The mixture was cooled to −20° C., and AcCl (0.315 mL, 4.41 mmol) was added carefully. The mixture was stirred for 20 min at −20° C., and CH2Cl2 was added. The mixture was washed with aq. 1M HCl and aq. 1M NaOH. The org. layer was dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (EtOAc/heptane 1:4→1:3→1:2) yielded the title compound (3.03 g, 98%). LC-MS: tR=1.18 min; ES+: 738.14.

Provenance & Evidence