Triethylamine → 2-Diazonio-3-oxo-1-[2-(trimethylsilyl)ethoxy]but-1-en-1-olate

HRID 2119199Notes

Reaction equation

HRID 2119199 reaction equation
[C:1]([O:7][CH2:8][CH2:9][Si:10]([CH3:13])([CH3:12])[CH3:11])(=[O:6])[CH2:2][C:3]([CH3:5])=[O:4].C(N(CC)CC)C.C1(C)C=CC(S([N:30]=[N+:31]=[N-])(=O)=O)=CC=1>C(#N)C>[N+:30](=[C:2]([C:3]([CH3:5])=[O:4])[C:1]([O:7][CH2:8][CH2:9][Si:10]([CH3:11])([CH3:13])[CH3:12])=[O:6])=[N-:31]

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 13661p-Toluenesulfonyl azideHCID 11481114HCID 11481114, compound

Product 1

HCID 540938322-Diazonio-3-oxo-1-[2-(trimethylsilyl)ethoxy]but-1-en-1-olateYield 84.6%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a solution of trimethylsilylethyl acetoacetate (10.6 g, 50.0 mmol) and triethylamine (7.10 mL, 51.5 mmol) in acetonitrile (85 mL) was added in an ice-bath p-toluenesulfonyl azide (10.0 g, 50.7 mmol) and the reaction mixture stirred at room temperature for 20 h. After evaporation of the solvent in vacuo, the residue was extracted with Et2O (90 mL) and this extract was washed with a solution of KOH (3.0 g) in H2O (83 mL) and again a solution of KOH (0.9 g) in H2O (30 mL), then brine, and dried (Na2SO4). Evaporation of the solvent in vacuo gave 11.6 g of a crude oil which was purified by column chromatography (SiO2, 150 g) eluting with 20% EtOAc/Hexanes, to obtain 9.65 g (42.3 mmol, yield 84.5%) of the title compound as yellowish oil: Rf 0.44 (20% EtOAc/Hex); ir (neat)νmax : 2130 (C=N2), 1715 (ester), and 1660 (ketone) cm-1 ; uv (CH2Cl2)λmax : 257 nm (ε7200); 1Hmr (CDCl3)δ: 0.07 (9H, s, SiMe3), 1.03 (2H, `t` J=8 Hz, CH2Si), 2.47 (3H, s, COCH3), and 4.30 (2H, `t` J=8 Hz, CO2CH2 ppm.

Workup

  1. customAfter evaporation of the solvent in vacuo
  2. extractionthe residue was extracted with Et2O (90 mL)
  3. washthis extract was washed with a solution of KOH (3.0 g) in H2O (83 mL)
  4. dry with materialagain a solution of KOH (0.9 g) in H2O (30 mL), then brine, and dried (Na2SO4)
  5. customEvaporation of the solvent in vacuo
  6. customgave 11.6 g of a crude oil which
  7. customwas purified by column chromatography (SiO2, 150 g)
  8. washeluting with 20% EtOAc/Hexanes

Sources & evidence

ORD record
ord-31d616cb221f4e15b31bdaa144a521a2
Source dataset
uspto-grants-1987_07
Patent number
US04683296

Reaction notes

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