Methyl iodide → 2,10-Dimethyl-4-(4-methyl-1-piperazinyl)-10H-thieno-[2,3-b][1,5]benzodiazepine

Participants

Reaction Conditions

Reaction Steps

A solution of 2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno[2,3-b][1,5]benzodiazepine (3.1 g) (European Patent Publication 0 454 436) in dry tetrahydrofuran (distillated from sodium/benzophenone) was stirred and cooled to -70° C. Tetramethylethylenediamine (1.16 g) was added followed by n-butyllithium (6.25 ml, 0.6M solution), keeping the temperature below -60° C. The deep red solution was stirred for 15 minutes and then methyl iodide (1.42 g) was added. The reaction was allowed to attain room temperature, during which time the red colour discharged. Water was added and the product extracted with ethyl acetate. The solvent was washed with water, dried and evaporated to dryness under reduced pressure. The product was purified by chromatography on Florisil using ethyl acetate as eluent and crystallised from acetronitrile to give the title compound, m.p. 126-128° C.

Provenance & Evidence