Methanol → HCID 21314184, compound

Participants

Reaction Conditions

Reaction Steps

To an ice cold solution of 3-chloro-3-methyl-8-oxo-7-(2-phenylacetamido)-5-thia-1-azabicyclo[4.2.0]octane-2-carboxylic acid, p-nitrobenzyl ester (5.04 g, 10 mmoles) in 100 ml of dichloromethane, are added in rapid succession phosphorus pentachloride (3.1 g, 15 mmoles) and N,N-dimethylaniline (1.8 g, 15 mmoles). The mixture is stirred at 0°C. for 15 minutes and at 25°C. for 3 hours, then 30 ml. of absolute methyl alcohol is added and the solution is further stirred for 1 hour. The solvent is flash evaporated. To the residue are added 25 ml. of ethyl acetate and 30 ml. of water and the mixture is stirred thoroughly. The crystalline solid thus obtained is filtered and air dried to give 2.75 g (65.2 per cent yield) of product, which decomposes above 160°C. NMR (DMSO-D6) ppm (δ), 1.74 (s, 3,3-CH3), 3.38 (ABq, δ 0.45 ppm, J 9 cps, 2--CH2), 4.92 (s, 1, 4H), 5.0 (d, 1, 6H), 5.34 (d, 1, 7H), 5.51 (s, 2, CO2CH2 ), 8.05 (ABq, δ 0.525 ppm, J 5 cps, p-NO2 --C6H4).

Provenance & Evidence