2,8,9-trimethyl-2,5,8,9-tetraza-1-phosphabicyclo[3.3.3]undecane

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: Add 2,8,9-trimethyl-2,5,8,9-tetraaza-1-phosphabicyclo[3.3.3]undecane (3.17 g, 14.7 mmol) as a solution using acetonitrile (10 mL) to a solution of 2-(4-bromo-phenyl)-4-(2-iodo-ethyl)-5-methyl-oxazole (See Intermediate 30) (4.38 g, 11.1 mmol) in 2.8:1 acetonitrile:THF (190 mL). After 4 hrs, concentrate under reduced pressure and add EtOAc and water to the residue. Separate the layers and extract the aqueous material with EtOAc. Wash the crude organic extract with water, dry over MgSO4, filter and concentrate. Purify on silica gel eluting with 7% EtOAc to give 2-(4-bromo-phenyl)-5-methyl-4-vinyl-oxazole (2.31 g, 83%): 1H NMR (400 Hz): (CDCl3) δ 7.89 (d, 2H, J=8 Hz), 7.57 (d, 2H, J=8 Hz), 6.54 (dd, 1H, J=17, 11 Hz), 5.93 (dd, 1H, J=17, 2 Hz), 5.29 (dd, 1H, J=11, 2 Hz), 2.40 (s, 3H). concentrate under reduced pressure add EtOAc and water to the residue Separate the layers extract the aqueous material with EtOAc Wash the crude organic extract with water dry over MgSO4 filter concentrate Purify on silica gel eluting with 7% EtOAc

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

Procedure: A solution of 0.3 g (0.53 mmol) of (R)-2-[4-(N-phenylcarbonylamidino)-phenylaminomethyl]-1-methyl-5-[1-(ethoxycarbonylmethylamino)-1-(pyrrolidinocarbonyl)-ethyl]-benzimidazole in 5 ml of n-butanol is mixed with 0.1 g (0.46 mmol) of 2,8,9-trimethyl-1-phospha-2,5,8,9-tetraazabicyclo[3.3.3]undecane and stirred for 1 hour at room temperature. The reaction mixture is purified on silica gel, eluting with ethyl acetate/ethanol/conc. ammonia (50:0.95:0.05 and 20:0.95:0.05). The uniform fractions are combined and concentrated by evaporation. The reaction mixture is purified on silica gel eluting with ethyl acetate/ethanol/conc concentrated by evaporation