Dimethylformamide dimethyl acetal → HCID 20239775, compound

Participants

Reaction Conditions

Reaction Steps

A mixture containing rac-4-[2-(4,5-dihydro-1H-imidazol-2-yl)ethyl]hexahydro-1H-azepine (1.95 g, 0.01M), methanol (50 ml) and dimethylformamide dimethylacetal (36 ml) was heated at 90° C. for 8 hrs. The excess of dimethylformamide dimethylacetal was removed in vacuo to give 4-[2-(4,5-dihydro-1H-imidazol-2-yl)ethyl]hexahydro-1H-azepine-1-carboxaldehyde dimethylacetal to the mixture of 6-aminopenicillanic acid (1.95 g, 0.009M) and diisopropylethylamine (1.52 ml) in dry chloroform (25 ml) was added the solution fo the above hexahydroazepine carboxaldehyde dimethylacetal in dry chloroform (10 ml) at 0° C. The reaction was stirred at 0° C. for 1 hr. and at room temperature for 3 hrs. After the reaction solvent was removed and the residue dissolved in water (30 ml). The aqueous solution, washed with ethylacetate was acidified to pH 3 with dil. HCl and purified on Sephadex LH 20 columns to give [ 2S-(2alpha,5alpha,6beta)]-6-[[[4-[2-(4,5-dihydro-1H-imidazol-2-yl)ethyl]hexahydro-1H-azepin-1-yl]methylene]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid hydrochloride (1.03 g, 27% yield).

Provenance & Evidence