Chlorotrimethylsilane → 1-Ethoxycarbonyl-4-trimethylsilylpiperazine

HRID 2164814Notes

Reaction equation

HRID 2164814 reaction equation
[CH2:1]([O:3][C:4]([N:6]1[CH2:11][CH2:10][NH:9][CH2:8][CH2:7]1)=[O:5])[CH3:2].C([Li])CCC.Cl[Si:18]([CH3:21])([CH3:20])[CH3:19]>O1CCCC1.CCCCCC>[CH2:1]([O:3][C:4]([N:6]1[CH2:7][CH2:8][N:9]([Si:18]([CH3:21])([CH3:20])[CH3:19])[CH2:10][CH2:11]1)=[O:5])[CH3:2]

Participants

6

Reactant 3

HCID 6397ChlorotrimethylsilaneHCID 84311-Piperazinecarboxylic acid, ethyl esterHCID 178418339Butyllithium

Product 1

HCID 133449251-Ethoxycarbonyl-4-trimethylsilylpiperazine

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 8058HexaneSolvent

Procedure

A solution of 20 g of 1-ethoxycarbonylpiperazine in 400 ml dry tetrahydrofuran is cooled to -65° and 61.5 ml of 2.1M solution of n-butyllithium in hexane is added dropwise over a period of 15 minutes. The mixture is stirred for 15 minutes and a solution of 16.44 ml of chlorotrimethylsilane in 68 ml of tetrahydrofuran is added dropwise over a period of 15 minutes. The mixture is then allowed to warm up to room temperature overnight and evaporated to dryness. Ethyl ether is added, the solids are filtered off, the filtrate is evaporated to dryness and the residue is distilled to give 1-ethoxycarbonyl-4-trimethylsilylpiperazine, b.p. 102°-107°/0.1 mm/Hg.

Workup

  1. customevaporated to dryness
  2. additionEthyl ether is added
  3. filtrationthe solids are filtered off
  4. customthe filtrate is evaporated to dryness
  5. distillationthe residue is distilled

Sources & evidence

ORD record
ord-fb3e14900ad3475596abab115883a416
Source dataset
uspto-grants-1985_03
Patent number
US04507311

Reaction notes

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