Sodium Bicarbonate → [2-Methyl-2-(2-methyl-1-pyrrolidinyl)-1-phenylpropyl]amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-methyl-2-(2-methyl-1-pyrrolidinyl)propanenitrile D25 (2.82 g; 18.56 mmol) in THF (100 ml) at −70° C. under argon was added over 15 minutes a solution of phenyllithium in dibutylether (20.6 ml of a 1.8M solution; 37.11 mmol). The reaction mixture was stirred at −70° C. for 2 hours then allowed to warm to room temperature and stirred overnight. Saturated aqueous sodium hydrogen carbonate (100 ml) was added and stirring continued for a further 10 minutes. The mixture was extracted with diethyl ether (2×150 ml). Combined organics were dried (Na2SO4) and evaporated in vacuo. The residual yellow oil was dissolved in methanol (100 ml) and sodium borohydride (2.12 g; 0.056 mol) added portionwise over 5 minutes. The reaction mixture was stirred at room temperature for 4 hours, further sodium borohydride (1 g; 0.026 mol) added and the mixture heated at 60° C. for 1.5 hours. The mixture was cooled and excess sodium borohydride decomposed by dropwise addition of water. The reaction mixture was evaporated in vacuo and the residue partitioned between saturated sodium hydrogen carbonate (150 ml) and DCM (150 ml). Solid potassium carbonate was added and the aqueous layer extracted with DCM (150 ml) Combined organic extracts were dried (Na2SO4) and evaporated to give a green oil. This was divided into 8 portions and each portion passed down a 10 g SCX column. After washing each column with DCM, 50% DCM in methanol and methanol the product was eluted with 1 M ammonia in methanol to yield the title compound as a pale yellow oil (3.46 g: 80%). Mass spectrum (Electrospray LC/MS), ES+: Found 233 (MH+). C15H24N2 requires 232. Ret. times 0.96 and 1.07 min.

Provenance & Evidence