1,4-Dimethylpiperazine-2,3-dione → Bis(3-methylphenyl)ethane-1,2-dione

HRID 1176948Notes

Reaction equation

HRID 1176948 reaction equation
CN1CCN(C)[C:4](=[O:9])[C:3]1=[O:10].[C:11]1([CH3:19])[CH:16]=[CH:15][CH:14]=[C:13]([Mg]Cl)[CH:12]=1>C1COCC1>[CH3:19][C:11]1[CH:16]=[C:15]([C:3]([C:4]([C:13]2[CH:14]=[CH:15][CH:16]=[C:11]([CH3:19])[CH:12]=2)=[O:9])=[O:10])[CH:14]=[CH:13][CH:12]=1

Participants

4

Reactant 2

HCID 3229831,4-Dimethylpiperazine-2,3-dione2×HCID 178425419HCID 178425419, compound

Product 1

HCID 13138799Bis(3-methylphenyl)ethane-1,2-dioneYield 35%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Mueller-Westerhoff9 and co-workers reported a simple, high-yield two-step synthesis of symmetrically substituted α-diones. The first step involves the preparation of 1,4-dimethylpiperazine-2,3-dione (13). Compound 13 was prepared in high yield from the reaction between N,N′-dimethylethylenediamine and diethyl oxalate in anhydrous diethyl ether at room temperature overnight. Second, compound 13 reacts with 2 equivalents of organolithium or Grignard compounds to form symmetrically-substituted α-diones after hydrolysis. 3,3′-Dimethylbenzil was prepared from the reaction between compound 13 and 2 equivalents of m-tolylmagnesium chloride in dry THF, followed by acidic workup in 35% yield (not optimized). Bis[1,2-di(3-methylphenyl)ethane-1,2-dithiolene]nickel (17) was then prepared by Schrauzer and Mayweg procedure as shown in FIG. 8.10

Workup

  1. customto form symmetrically-substituted α-diones
  2. customafter hydrolysis

Sources & evidence

ORD record
ord-6539142bef8842c29ee12e554898cad3
Source dataset
uspto-grants-2010_11
Patent number
US07842830B2

Reaction notes

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