Hexane → p-Toluenesulfonic acid

Participants

Reaction Steps

Diphenylmethyl-3-[(1-methyl-1H-tetrazol-5-yl) thiomethyl]-7α-methylthio-7β-(4-nitrobenzylideneamino)-1-oxadethia-ceph-3-em-4-carboxylate (471 mg; 0.72 mmol) was dissolved in ethyl acetate (2 ml) and a solution of toluene-p-sulphonic acid monohydrate (149 mg; 0.78 mmol) in a little ethyl acetate added. After stirring at room temperature for 1 hour, hexane was added to complete the precipitation of the product, which was filtered off, washed well with ethyl acetate, ether and dried in vacuo to give diphenylmethyl 7-β-amino-3-[(1-methyl-1H-tetrazol-5-yl)thiomethyl]-7α-methylthio-1-oxadethia-ceph-3-em-4-carboxylate, p-toluene sulphonic acid salt (431 mg; 93%). νmax (Nujol) 3400, 1795, 1720, 1620 cm-1 ; δppm [(CD3)2SO] 2.28 (3H,s), 2.41 (3H,s), 3.4-3.6(3H, broad s), 3.89 (3H,s), 4.28(2H, AA1), 4.72 and 4.87 (2H, ABq, J19 Hz), 5.44(1H,s), 6.88(1H,s), 7.1-7.7(14H,m). The salt was suspended in ethyl acetate, treated with dilute sodium hydrogencarbonate solution and the organic phase separated, washed with brine, dried and evaporated to give the title compound (253 mg; 80%). νmax (CHCl3 ) 3375, 1785, 1720, 1625 cm-1 ; δppm (CDCl3) 2.09 (2H, broad s), 2.33 (3H,s), 3.85(3H,s), 4.30(2H,AA1), 4.63 and 4.80 (2H,ABq, J18.8 Hz), 4.88(1H,s), 6.92(1H,s), 7.2-7.6 (10H,m).

Provenance & Evidence