Diketene → diethyl N-(2,4-dimethoxybenzyl)-3-hydroxy-3-methyl-5-oxo-2,2-pyrrolidine-dicarboxylate

HRID 1388874Notes

Reaction equation

HRID 1388874 reaction equation
[CH3:1][O:2][C:3]1[CH:21]=[C:20]([O:22][CH3:23])[CH:19]=[CH:18][C:4]=1[CH2:5][NH:6][CH:7]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[C:8]([O:10][CH2:11][CH3:12])=[O:9].[CH2:24]=[C:25]1[O:29][C:27](=[O:28])[CH2:26]1>C(O)(=O)C>[CH2:16]([O:15][C:13]([C:7]1([C:8]([O:10][CH2:11][CH3:12])=[O:9])[C:25]([OH:29])([CH3:24])[CH2:26][C:27](=[O:28])[N:6]1[CH2:5][C:4]1[CH:18]=[CH:19][C:20]([O:22][CH3:23])=[CH:21][C:3]=1[O:2][CH3:1])=[O:14])[CH3:17]

Participants

4

Reactant 2

HCID 12661DiketeneHCID 13422978Diethyl {[(2,4-dimethoxyphenyl)methyl]amino}propanedioate

Product 1

HCID 13422981diethyl N-(2,4-dimethoxybenzyl)-3-hydroxy-3-methyl-5-oxo-2,2-pyrrolidine-dicarboxylateYield 60%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

39.6 g (0.122 moles) of diethyl (2,4-dimethoxy-benzyl-amino)-malonate prepared according to Example (1c) are boiled with 12.3 g (11.2 ml, 0.146 moles) of diketene in 80 ml of glacial acetic acid for half an hour. The glacial acetic acid is distilled off on water bath, in vacuo, the residual oil is crystallized by trituration with 150 ml of water, whereupon the substance is dissolved in 60 ml of ethyl acetate and recystallized by addition of petroleum ether. 29.6 g (60%) of diethyl-N-(2.4-dimethoxybenzyl)-3-hydroxy-3-methyl-5-oxo-2,2-pyrrolidine-dicarboxylate and/or the tautomer thereof are obtained. Melting point: 106° to 107° C.

Workup

  1. distillationThe glacial acetic acid is distilled off on water bath, in vacuo
  2. customthe residual oil is crystallized by trituration with 150 ml of water, whereupon the substance
  3. dissolutionis dissolved in 60 ml of ethyl acetate
  4. additionrecystallized by addition of petroleum ether

Sources & evidence

ORD record
ord-47c12de85b80438997e037db761466e3
Source dataset
uspto-grants-1984_02
Patent number
US04434099

Reaction notes

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