Ammonia → 1-[2-(4,5,10,11-tetrahydro-1H-dibenzo[a,d]cyclohepten-5-yl)ethyl]pyrrolidine

Participants

Reaction Steps

10.4 g of lithium are added to a mixture of 2.6 l of dry ammonia and 1.6 l of dry tetrahydrofuran at -50° under an argon atmosphere. After 2.5 minutes, the deep blue solution is treated while stirring well at -50° to -43° over a period of 6 minutes with a solution, pre-cooled to -50°, of 150 g of 1-[2-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl)ethyl]pyrrolidine and 351 g of t-butanol in 1.8 l of dry tetrahydrofuran. After completion of the addition, the dark blue mixture is stirred at -43° to -39° until decolorization has occurred (about 10 minutes). After an additional 2 minutes, the mixture is treated with 12.0 g of sodium benzoate and subsequently the ammonia is removed. The residue is subsequently washed six times with 500 ml of saturated sodium chloride solution each time, dried over magnesium sulfate and evaporated in vacuo. The light brown oil obtained is purified by column chromatography on 500 g of aluminium oxide (activity grade II, neutral) using benzene for the elution, there being obtained crude 1-[2-(4,5,10,11-tetrahydro-1H-dibenzo[a,d]cyclohepten-5-yl)ethyl]pyrrolidine as a light yellow oil which crystallizes slowly upon standing.

Provenance & Evidence