Methyltriphenylphosphonium iodide → benzyl (S)-1-((1S,2R,4R)-4-amino-2-ethylcyclohexyl)-2-oxopyrrolidin-3-ylcarbamate

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Reaction Steps

Following the procedures described in Example 2a, Steps 1–4, and substituting methyl triphenylphosphonium iodide in Step 1, (1R,2S,5R)-2-benzyloxycarbonylamino-7-oxo-6-aza-bicyclo[3.2.1]octane-6-carboxylic acid tert-butyl ester was converted to {(3S)-1-[(1S,2R,4R)-4-tert-butoxycarbonylamino-2-ethyl-cyclohexyl]-2-oxo-pyrrolidin-3-yl}-carbamic acid benzyl ester. A portion of this material (995 mg, 2.2 mmol) was dissolved in 20 mL of 4:1 CH2Cl2/TFA. The resultant solution was stirred at RT for 3 h and concentrated in vacuo. The residue was dissolved in methylene chloride and concentrated in vacuo; this procedure was repeated twice more to afford benzyl (S)-1-((1S,2R,4R)-4-amino-2-ethylcyclohexyl)-2-oxopyrrolidin-3-ylcarbamate. MS found: (M+H)+=360.2.

Provenance & Evidence