Water → (R)-5-Biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butylester

HRID 588293Notes

Reaction equation

HRID 588293 reaction equation
[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH2:13][C:14]2[CH:19]=[CH:18][C:17]([C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=3)=[CH:16][CH:15]=2)[CH2:11]/[C:10](=[CH:26]\N(C(C)C)C(C)C)/[C:9]1=[O:34])=[O:7])([CH3:4])([CH3:3])[CH3:2].S(=O)(=O)(O)O.O>C1COCC1>[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH2:13][C:14]2[CH:15]=[CH:16][C:17]([C:20]3[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=3)=[CH:18][CH:19]=2)[CH2:11][C:10](=[CH2:26])[C:9]1=[O:34])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

5

Reactant 3

HCID 962WaterHCID 1118Sulfuric AcidHCID 58160400(r)-5-Biphenyl-4-ylmethyl-3-[1-diisopropylamino-meth-(e)-ylidene]-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester

Product 1

HCID 46193438(R)-5-Biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butylester

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
10 °C

Procedure

Crude (R)-5-biphenyl-4-ylmethyl-3-[1-dimethylaminometh-(E/Z)-ylidene]-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (7-a, R1=Boc, R6=Me, R7=Me) (66.7 g) is dissolved in THF (340 ml) and cooled to 10° C. Sulphuric acid (96%; 6.9 ml) is added followed by water (152 ml). The mixture is stirred at room temperature for 0.5 h. Phases are separated. The organic phase is added to formaldehyde solution (37% in water; 138 ml). 1% Tetra-n-butylammoniumhydroxide solution (14.2 ml) is added. Potassium carbonate (27.8 g) is added portionwise over 0.5 h. Sodium hydroxide solution (15.1 g) is added over 3 h, maintaining pH 10.5. The phases are separated. The organic phase is washed with water (100 ml) followed by sodium bisulfite solution (21.4 g). Toluene (100 ml) and sodium chloride solution (50 ml) added. The phases are separated. The organic phase is extracted with sodium chloride solution (20%; 50 ml), dried (Na2SO4) and concentrated in vacuo to give (R)-5-Biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (4-a, R1=Boc) (63 g). Material can be recrystallised as follows: crude (R)-5-biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (4-a, R1=Boc) (58.4 g) is dissolved in methanol (525 ml) at 50° C. Water (175 ml) is added and the mixture is cooled to 0° C. The solid is collected by filtration and the cake washed with a mixture of methanol (53 ml) and water (18 ml). The solid is then dried in vacuo, giving (R)-5-biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (4-a, R1=Boc). Spectroscopic data as in Example 23.

Workup

  1. customPhases are separated
  2. additionThe organic phase is added to formaldehyde solution (37% in water; 138 ml)
  3. addition1% Tetra-n-butylammoniumhydroxide solution (14.2 ml) is added
  4. additionPotassium carbonate (27.8 g) is added portionwise over 0.5 h
  5. additionSodium hydroxide solution (15.1 g) is added over 3 h
  6. temperaturemaintaining pH 10.5
  7. customThe phases are separated
  8. washThe organic phase is washed with water (100 ml)
  9. additionToluene (100 ml) and sodium chloride solution (50 ml) added
  10. customThe phases are separated
  11. extractionThe organic phase is extracted with sodium chloride solution (20%; 50 ml)
  12. dry with materialdried (Na2SO4)
  13. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-6e9052917a8a4a2197c4d2af5e6e6c6d
Source dataset
uspto-grants-2016_01
Patent number
US09227934B2

Reaction notes

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