Chlorotrimethylsilane → HCID 178431922, compound

Participants

Reaction Steps

To a stirred solution of 1.2 g (5 mmoles) of 6-amino-2,2-dimethyl-3-(5-tetrazolyl)penam, 1.0 g (10 mmole) of triethylamine and 30 ml of dichloromethane, cooled to 0° C., is added 0.54 g (5 mmole) of chlorotrimethylsilane. After 15 minutes, 0.86 (5 mmole) of 1-(dimethoxymethyl)hexahydroazepine (British Patent No. 1,293,590) is added, and stirring is continued for a further 1 hour. The volatile components are removed by evaporation in vacuo, and then the residue is extracted with 25 ml of acetone. The insoluble material is filtered off, and the acetone is evaporated in vacuo to a yellow foam, which changes to a white powder on trituration with ether. This affords 1.44 g (82% yield) of 6-([hexahydro-1-azepinyl]methyleneamino)-2,2-dimethyl-3-(5-tetrazolyl)penam. The infrared spectrum of the product (KBr disc) shows absorption bands at 1795 cm-1 (β-lactam), 1706 cm-1 and 1645 cm-1. The NMR spectrum (CDCl3) shows absorption bands at 8.00 ppm (singlet, 1H, N--CH=N), 5.90 and 5.60 ppm (two doublets, 2H, J = 4 Hz, C-5 and C-6 hydrogens), 5.40 ppm (singlet, 1H, C-3 hydrogen), 3.90-3.50 (multiplet, 4H, CH2 --N--CH2), 2.00-1.50 ppm (multiplet, 11H, C-2 methyl hydrogens and [CH2 ]4) and 1.20 ppm (singlet, 3H, C-2 methyl hydrogens). Examination of the product by thin-layer chromatography (0.2M NaOAc: acetone; 1:6) showed a single spot (Rf 0.23).

Provenance & Evidence