N-trimethylsilylbenzamide

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6.4 ml of hexamethyldisilazane (31 mmoles) were added to a refluxing mixture of 15 ml of toluene, 40 mg of saccharin (0.22 mmole) and 5.0 g of benzamide (41.3 mmoles) and the ammonia liberated was led into water by a stream of nitrogen passed over the reaction mixture. Titration with 1 N H2SO4 revealed that the calculated amount of ammonia was evolved in 15 minutes and solvent and excess hexamethyldisilazane were evaporated in vacuo to obtain 8.04 g (101%) of N-trimethylsilylbenzamide melting at 111°-115° C. The experiment was repeated without the addition of saccharin and it was found that 82% of the theoretical amount of ammonia was evolved in 15 minutes and 88% of it in 50 minutes. solvent and excess hexamethyldisilazane were evaporated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 601.5 mg (1.73 mmoles) of 3-methyl-7-phenylacetamido-3-cephem-4-carboxylic acid-1-oxide were silylated by refluxing in 50 ml of dichloromethane for one hour with 503 mg (2.61 mmoles) of N-trimethylsilylbenzamide. 0.1 g of amidosulfonic acid (1 mmole) were added to the clear, slightly yellow solution obtained and after cooling in an ice-bath, bromination was carried out in half an hour with 464.8 mg (2.61 mmoles) of N-bromosuccinimide to obtain a yield of 42% of trimethylsilyl 3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylate-1-oxide. obtained after cooling in an ice-bath

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 458 mg of 3-methyl-7-phenylacetamido-3-cephem-4-carboxylic acid-1-oxide (1.32 mmoles) were silylated in 40 ml of dichloromethane with 397 mg (2.06 mmoles) of N-trimethylsilylbenzamide by refluxing for half an hour and the clear, pale yellow solution was cooled in an ice-bath. Bromination was carried out in half an hour with 378.5 mg (2.13 mmoles) of N-bromosuccinimide as the brominating agent to obtain a 42% yield of trimethylsilyl 3-bromomethyl-7-phenylacetamido-3-cephem-4-carboxylate-1-oxide. by refluxing for half an hour the clear, pale yellow solution was cooled in an ice-bath

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6.4 ml of hexamethyldisilazane (31 mmoles) were added to a refluxing mixture of 15 ml of toluene, 40 mg of saccharin (0.22 mmole) and 5.0 g of benzamide (41.3 mmoles) and the ammonia liberated was led into water by a stream of nitrogen passed over the reaction mixture. Titration with 1 N H2SO4 revealed that the calculated amount of ammonia was evolved in 15 minutes and solvent and excess hexamethyldisilazane were evaporated in vacuo to obtain 8.04 g (101%) of N-trimethylsilylbenzamide melting at 111°-115° C. The experiment was repeated without the addition of saccharin and it was found that 82% of the theoretical amount of ammonia was evolved in 15 minutes and 88% of it in 50 minutes. solvent and excess hexamethyldisilazane were evaporated in vacuo