Carbonazidic acid, 1,1-dimethylethyl ester → Tert-butyl 4-benzylpiperazine-1-carboxylate

HRID 1389989Notes

Reaction equation

HRID 1389989 reaction equation
[CH3:1][C:2]([CH3:10])([O:4][C:5]([N:7]=[N+]=[N-])=[O:6])[CH3:3].[C:11]1([CH2:17][N:18]2[CH2:23][CH2:22]N[CH2:20][CH2:19]2)[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1>N1C=CC=CC=1.O.CCOCC>[CH3:1][C:2]([CH3:10])([O:4][C:5]([N:7]1[CH2:20][CH2:19][N:18]([CH2:17][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH2:23][CH2:22]1)=[O:6])[CH3:3]

Participants

6

Reactant 2

HCID 61256Carbonazidic acid, 1,1-dimethylethyl esterHCID 759941-Benzylpiperazine

Product 1

HCID 584330Tert-butyl 4-benzylpiperazine-1-carboxylateYield 68%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 1049PyridineSolvent2×HCID 3283Diethyl EtherSolvent2×

Procedure

A solution of 3.4 g (0.024 mole) of 1,1-dimethylethoxy carbonylazide in 5 ml of pyridine was rapidly added to a stirred solution of 1-phenylmethylpiperazine (4.2 g, 0.024 mole) in 5 ml of pyridine. An initial exothermic reaction was noted. The mixture was allowed to stir overnight, diluted with water and the product was extracted with two 50 ml portions of ether. The ether extracts were dried (MgSO4), filtered, and evaporated to yield a yellow oil. Column chromatography (2" diameter column, 500 g of silica gel, ether eluent) followed by sublimation at 110°/0.5 mm returned 5.7 g (86%) of white solid, m.p. 64°-73°. The solid was dissolved in 50 ml of ether and cooled to -70°. The resultant white solid was filtered off to yield 4.5 g (68%) of product, m.p. 71-3°. Calc. for C16H24N2O2 (276.38): C, 69.53; H, 8.75; N, 10.14. Found: C, 69.44; H, 8.82; N, 10.15.

Workup

  1. customAn initial exothermic reaction
  2. extractionthe product was extracted with two 50 ml portions of ether
  3. dry with materialThe ether extracts were dried (MgSO4)
  4. filtrationfiltered
  5. customevaporated
  6. customto yield a yellow oil
  7. customfollowed by sublimation at 110°
  8. temperaturecooled to -70°
  9. filtrationThe resultant white solid was filtered off

Sources & evidence

ORD record
ord-08a83942e567472081bf10f2a98df5de
Source dataset
uspto-grants-1981_01
Patent number
US04247549

Reaction notes

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