Reaction #2358492

Reaction equation

tert-butyl-3-(dimethylaminomethylene)-2-oxo-4,6a-dihydro-3aH-cyclopenta[b]pyrrole-1-carboxylate

hydrochloric acid

dioxane

→

desired compound

Yield 93.0%

Tert-butyl-3-(hydroxymethylene)-2-oxo-4,6a-dihydro-3aH-cyclopenta[b]pyrrole-1-carboxylate

Yield 93.0%

Solvents

ethyl acetate

Conditions

Workup

1. 1
   Washwashed with water and brine
2. 2
   Otherdried
3. 3
   Concentrationconcentrated

Procedure

A solution of tert-butyl-3-(dimethylaminomethylene)-2-oxo-4,6a-dihydro-3aH-cyclopenta[b]pyrrole-1-carboxylate III-1 (120 mg, 0.43 mmol) in dioxane (9 mL) was stirred with hydrochloric acid (2 M, 0.86 mL, 1.72 mmol) for 15 h at room temperature. The solution was diluted with ethyl acetate, washed with water and brine, dried, concentrated giving the desired compound as a colorless oil (101 mg, 93%); 1H NMR (400 MHz, CDCl3) 9.92 (1H, d), 7.05 (1H, d), 6.91 (1H, m), 5.71 (1H, m), 5.07 (1H, d), 3.46 (1H, dt), 2.87 (1H, dd), 2.31 (1H, m), 1.55 (9H, s). LCMS (Method A): 0.79 min; ES−250 (M−H+).

Source