Dimethyl Sulfoxide → 4-Carbobenzoxy-1-(o-nitrophenyl)piperazine-2-carboxylic acid

HRID 372199Notes

Reaction equation

HRID 372199 reaction equation
[C:1]([N:11]1[CH2:16][CH2:15][NH:14][CH:13]([C:17]([OH:19])=[O:18])[CH2:12]1)([O:3][CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1)=[O:2].[N+:20]([C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][C:24]=1F)([O-:22])=[O:21].C(N(CC)CC)C.CS(C)=O>O.C1C=CC=CC=1.C(O)(=O)C>[C:1]([N:11]1[CH2:16][CH2:15][N:14]([C:24]2[CH:25]=[CH:26][CH:27]=[CH:28][C:23]=2[N+:20]([O-:22])=[O:21])[CH:13]([C:17]([OH:19])=[O:18])[CH2:12]1)([O:3][CH2:4][C:5]1[CH:6]=[CH:7][CH:8]=[CH:9][CH:10]=1)=[O:2]

Participants

8

Reactant 4

HCID 679Dimethyl SulfoxideHCID 8471TriethylamineHCID 738951-Fluoro-2-nitrobenzeneHCID 50583624-((Benzyloxy)carbonyl)piperazine-2-carboxylic acid

Product 1

HCID 121096434-Carbobenzoxy-1-(o-nitrophenyl)piperazine-2-carboxylic acid

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolventHCID 241BenzeneSolventHCID 962WaterSolvent

Procedure

A mixture of 12.0 g. (0.04 mole) of 4-carbobenzoxypiperazine-2-carboxylic acid, 8.4 g. (0.06 mole) of o-nitrofluorobenzene, 16 g. of triethylamine and 100 ml. of dimethylsulfoxide is heated at 90° for 8 1/2 hours, cooled, diluted with water (300 ml.) and extracted with ether. The aqueous phase is then acidified with dilute hydrochloric acid and extracted with ether. The combined ether extracts are diluted with 1/3 its volume of pentane. The ether-pentane solution is washed with water, dried (MgSO4) and concentrated to give 14 g. of yellow-orange glassy product. Thin layer chromatrgraphy analysis (1% acetic acid in benzene on a silica gel plate) shows 1 main spot with a faint second impurity spot.

Workup

  1. additionA mixture of 12.0 g
  2. temperaturecooled
  3. extractionextracted with ether
  4. extractionextracted with ether
  5. additionThe combined ether extracts are diluted with 1/3 its volume of pentane
  6. washThe ether-pentane solution is washed with water
  7. dry with materialdried (MgSO4)
  8. concentrationconcentrated
  9. customto give 14 g

Sources & evidence

ORD record
ord-a0edf31317c248e5b4191da6c11de254
Source dataset
uspto-grants-1978_05
Patent number
US04089958

Reaction notes

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