1,1'-(Diazomethylene)bis(benzene) → (S)-7-[[Ethoxy(4-phenylbutyl)phosphinyl]acetyl]-1,4-dithia-7-azaspiro[4.4]nonane-8-carboxylic acid, diphenylmethyl ester

Participants

Reaction Steps

(S)-7-[[Ethoxy(4-phenylbutyl)phosphinyl]acetyl]-1,4-dithia-7-azaspiro[4.4]nonane-8-carboxylic acid (3.2 g) in ethyl acetate is treated with 2.0 g of diphenyldiazomethane in ethyl acetate. After 3.5 hours, the reaction mixture is partitioned between ethyl acetate and water. The layers are separated and the organic portion is washed with saturated sodium bicarbonate, 5% potassium bisulfate, brine and dried (MgSO4). The solvent is stripped leaving 6.1 g of residue which is chromatographed on 180 g of silica, eluting with ethyl acetate to yield 3.4 g of the title compound as an oil.

Provenance & Evidence