p-Nitrobenzyl 2-(4-ethylthio-2-oxo-1-azetidinyl)-2-chloroacetate → p-Nitrobenzyl 2-(4-ethylthio-2-oxo-1-azetidinyl)-2-[2-ethoxyethylthio(thiocarbonyl)thio]acetate

Participants

Reaction Steps

A solution of 3.58 g potassium 2-ethoxyethyl trithiocarbonate and 3.7 g benzyltriethylammonium chloride in 100 ml methylene chloride was cooled to 0° C. under a nitrogen atmosphere and a solution of 5.3 g of p-nitrobenzyl 2-(4-ethylthio-2-oxo-1-azetidinyl)-2-chloroacetate in 50 ml methylene chloride was added dropwise. The reaction mixture was stirred for 1 hour, then washed with three 50 ml portions of water, dried over anhydrous sodium sulfate and concentrated in vacuo to an oil. (8.6 g). The crude product was chromatographed on silica gel eluting with 5% ethyl acetate in chloroform to yield 2.3 g of the title compound as an oil. The IR spectrum of a chloroform solution of the title compound had an absorption at 5.65 micron; and the NMR spectrum in deuterochloroform showed peeks at 1.2(m, 6H); 2.34-3.77(c, 10H); 4.7,4.98(m, 1H); 5.26(s, 2H); 6.62, 6.86(s, 1H); 7.43(m, 2H); and 8.16(m, 2H). ppm.

Provenance & Evidence