Reaction #50541

Reaction equation

Ammonium chloride

2-phenyl-4-methyl-5-formylfuran

diphenylmethylpiperazine

sodium bicarbonate

Methyl magnesium iodide

→

1-(diphenylmethyl)-4-[(2-phenyl-4-methylfuran-5-yl)eth-1-yl]piperazine

Solvents

Diethyl ether

water

methylene chloride

Conditions

Workup

1. 1
   OtherThe residue was partitioned between methylene chloride/water
2. 2
   Otherthe organic layer separated
3. 3
   Dryingdried over anhydrous magnesium sulfate
4. 4
   Filtrationfiltered
5. 5
   Otherevaporated
6. 6
   OtherThe residue was flash-chromatographed on silica gel
7. 7
   Washeluting with 15% ethyl acetate in heptane with a trace of ammonia

Procedure

A solution of 2-phenyl-4-methyl-5-formylfuran (1.1 g), diphenylmethylpiperazine (1.5 g), and titanium(IV) isopropoxide (1.76 g) was stirred for 11/4 hours. Diethyl ether (20 ml) was added, and the resultant solution was stirred for 30 minutes. Methyl magnesium iodide (6 ml of 3M in ether) was then added dropwise, and the mixture stirred at room temperature for 1 hour. Ammonium chloride (20 ml of a saturated solution in water) was then added, followed by 300 ml of methylene chloride, and the mixture made basic with a solution of sodium bicarbonate. The residue was partitioned between methylene chloride/water, the organic layer separated, dried over anhydrous magnesium sulfate, filtered and evaporated. The residue was flash-chromatographed on silica gel, eluting with 15% ethyl acetate in heptane with a trace of ammonia, to yield 0.51 g of 1-(diphenylmethyl)-4-[(2-phenyl-4-methylfuran-5-yl)eth-1-yl]piperazine. Treatment with anhydrous hydrochloric acid in ethanol converted the base to its dihydrochloride salt, m.p. 205°-208° C.

Source