Reaction #75327

Reaction equation

L-alanyl-L-proline ethylamide hydrobromide

triethylamine

1-adamantoyl chloride

→

N-(1-adamantylcarbonyl)-L-alanyl-L-proline ethylamide

Yield 59.0%

Solvents

tetrahydrofuran

Conditions

Workup

1. 1
   Otherevaporated to dryness
2. 2
   workup.DISSOLUTIONThe oily residue was dissolved in ethyl acetate
3. 3
   Washthe solution washed successively with 0.5-N hydrochloric acid, water, 5% sodium bicarbonate solution and water
4. 4
   Dryingdried over sodium sulphate
5. 5
   Otherevaporated
6. 6
   OtherThe resulting oil was crystallised from ethyl acetate/petroleum ether

Procedure

2.93 g (0.010 mol) of L-alanyl-L-proline ethylamide hydrobromide were dissolved in 50 ml of tetrahydrofuran and the mixture was cooled to 0° C. There were then added 2.8 ml (0.020 mol) of triethylamine followed by 2.15 g (0.010 mol) of 1-adamantoyl chloride. The mixture was stirred at 0° C. for 0.5 hour and at room temperature for 2 hours and then evaporated to dryness. The oily residue was dissolved in ethyl acetate and the solution washed successively with 0.5-N hydrochloric acid, water, 5% sodium bicarbonate solution and water, dried over sodium sulphate and evaporated. The resulting oil was crystallised from ethyl acetate/petroleum ether to yield 2.2 g (59%) of N-(1-adamantylcarbonyl)-L-alanyl-L-proline ethylamide of melting point 116°-118° C; [α]D20 =-88.1° (c=0.99% in methanol).

Source