Ethyl chloroformate → Ethyl trans-2-phenylcyclopropanecarboxylate

Beteiligte Stoffe

Reaktionsschritte

To an ice cold solution of 1.62 g of (1R, 2R)-2-phenyl-cyclopropane carboxylic acid (from racemic trans-2-phenyl-cyclopropane carboxylic acid by resolution on a chiral HPLC column) and 2.0 mL of triethylamine and 0.12 g of 4-dimethylaminopyridine was added 1.2 mL of ethyl chloroformate The mixture was allowed to warm and stir for 1 h, then washed with 25 mL of 3N HCl, 25 mL of water, 25 mL of saturated sodium carbonate and dried over magnesium sulfate. Removal of solvents under reduced pressure gave 1.9 g of product as an oil: MS (m+1)=191.1; 1H NMR (400 MHz, CDCl3) 7.3 (dd, 2H), 7.2 (t, 1H), 7.1 (d, 2H), 4.18 (q, 2H), 2.5 (m, 1H), 1.9 (m, 1H), 1.6 (m, 1H), 1.3 (overlapping m and t, 4H).

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