Urea → Bromosuccinic acid, (-)-
Reaction equation
[Br-:1].[Na+].N[C@H:4]([C:9]([OH:11])=[O:10])[CH2:5][C:6]([OH:8])=[O:7].N([O-])=O.[Na+].NC(N)=O>S(=O)(=O)(O)O.O>[Br:1][C@@H:4]([CH2:5][C:6]([OH:8])=[O:7])[C:9]([OH:11])=[O:10]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- 5 °C
Procedure
To a solution of 1,000 g (9.72 mol) sodium bromide in 2.1 liters 6N sulfuric acid under nitrogen was added 323.1 g (2.43 mol) L-aspartic acid and the resulting solution cooled to 5° C. To this was added in portions over 1.5 hours, 201.4 g (2.92 mol) sodium nitrite while keeping the temperature below 10° C. After the addition was completed, one liter of distilled water was added, followed by 73.07 g (1.22 mol) urea. The resulting mixture was poured into a separatory funnel and extracted with 2.5 liters ethyl ether. To the aqueous layer was added 500 g sodium chloride, and the mixture extracted three times with ether (3×1.25 liters). The combined ether layers were washed with brine, dried (Na2SO4) and the solvent evaporated in vacuo to yield 303 g (63%) of the desired compound; [alpha]D =-73.5° (c=0.6 in ethyl acetate); m.p. 185° C.
Workup
- additionTo this was added in portions over 1.5 hours
- customthe temperature below 10° C
- additionAfter the addition
- additionThe resulting mixture was poured into a separatory funnel
- extractionextracted with 2.5 liters ethyl ether
- additionTo the aqueous layer was added 500 g sodium chloride
- extractionthe mixture extracted three times with ether (3×1.25 liters)
- washThe combined ether layers were washed with brine
- dry with materialdried (Na2SO4)
- customthe solvent evaporated in vacuo
Sources & evidence
- ORD record
- ord-cf6b65f57513483785d32cc26aadba44
- Source dataset
- uspto-grants-1991_05
- Patent number
- US05013729
Reaction notes
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