Yield:185692-51-7 100%

Reaction Conditions:

with trifluoroacetic acid in dichloromethane at 0 - 20; for 2 h;

Steps:

36.1 2-Benzyl-hexahydro-cyclopenta[c]pyrrol-4-one

To the solution of 2-cyclopenten-l -one (3.06 mL, 36.5 mmol) and N-Benzyl-N-(methoxymethyl)-N- trimethylsilylmethylamine (18.7 mL, 43.8 mmol) in DCM (75 mL) was added 1M TFA in DCM (3.5 mL) at 0°C. Reaction was slowly allowed to obtain room temperature. After 2 hours, saturated NaHC0₃ was added. Organic phase was separated and water phase was extracted twice with DCM. Combined organic phases were dried with sodium sulfate and concentrated to give compound (36a) without further purification (7.88 g, 36.5 mmol, 100%). MS m/z ([M+H]⁺) 216.

References:

WO2015/128334,2015,A1 Location in patent:Page/Page column 59