Chlorotrimethylsilane → 6-[[(1-Acetyl-2-pyrrolidinyl)carbonyl]-amino]-1,2-dihydro-2-oxo-3-quinolinecarboxylic acid

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Reaction Steps

A solution of 4.71 g (30 mmol) of N-acetyl-L-proline and 60 ml of dichloromethane is cooled to -18° and 3.3 ml (30 mmol) of N-methyl morpholine and 3.9 ml (30 mmol) of isobutyl chloroformate is added, and the reaction mixture is stirred for 30 minutes at -10° to -20°. A mixture of 4.08 g (20 mmol) of 6-amino-1,2-dihydro-2-oxo-3-quinolinecarboxylic acid, 150 ml of dichloromethane, 8.4 ml (60 mmol) of triethylamine, and 7.6 ml (60 mmol) of chlorotrimethylsilane is stirred at room temperature for 35 minutes. The silylation mixture is cooled to -20° and the mixed anhydride of proline is added and stirred with cooling overnight. The reaction mixture is evaporated to dryness, and the residue is treated with ethanol to yield 4.42 g of 6-[[(1-acetyl-2-pyrrolidinyl)carbonyl]-amino]-1,2-dihydro-2-oxo-3-quinolinecarboxylic acid, mp 303° dec.

Provenance & Evidence