Trimethylsilylacetylene → Methyl 4-trimethylsilylethynylbenzoate

HRID 1264227Notes

Reaction equation

HRID 1264227 reaction equation
[CH3:1][Si:2]([C:5]#[CH:6])([CH3:4])[CH3:3].C([Li])CCC.[CH3:12][O:13][C:14](=[O:22])[C:15]1[CH:20]=[CH:19][C:18](I)=[CH:17][CH:16]=1>C1COCC1.C(OCC)(=O)C.[Cl-].[Zn+2].[Cl-].C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:12][O:13][C:14](=[O:22])[C:15]1[CH:20]=[CH:19][C:18]([C:6]#[C:5][Si:2]([CH3:4])([CH3:3])[CH3:1])=[CH:17][CH:16]=1

Participants

8

Reactant 3

HCID 66111TrimethylsilylacetyleneHCID 69273Methyl 4-iodobenzoateHCID 178418339Butyllithium

Product 1

HCID 640161Methyl 4-trimethylsilylethynylbenzoateYield 100.1%

Reagents, catalysts & solvents 4

HCID 3007855ZincchlorideCatalystHCID 178418397HCID 178418397, compoundCatalystHCID 8028TetrahydrofuranSolvent2×HCID 8857Ethyl AcetateSolvent

Conditions

Temperature
20 °C

Procedure

To a cooled solution (−78° C.) of (trimethylsilyl)acetylene (4.2 mL, 30 mmol) in THF (25 mL) is added dropwise (2.5M) n-butyllithium (11.6 mL, 29 mmol) and stirred for 30 min followed by slow addition of (0.5M) zinc chloride (58 mL, 29 mmol). The resulting solution is allowed to warm to 20° C. followed by addition of 4-iodo-benzoic acid methyl ester (5.24 g, 20 mmol) (reference example 48) and tetrakis(triphenylphosphine)palladium(0) (1.16 g, 1 mmol) in THF (10 mL). The resulting mixture is heated to 55° C. and stirred for 2 hours then cooled to 20° C. The reaction mixture is diluted with ethyl acetate, washed with sat.NH4Cl soln, water and brine, dried over MgSO4 and concentrated to give 4.65 g of title compound. 1H NMR (CDCl3) δ 0.26 (s, 2H), 3.91 (s, 3H), 7.52 (d, J=8 Hz, 2H), 7.97 (d, J=8 Hz, 2H). MS (EI) m/z 232 (M+).

Workup

  1. temperatureThe resulting mixture is heated to 55° C.
  2. stirringstirred for 2 hours
  3. temperaturethen cooled to 20° C
  4. washwashed
  5. dry with materialNH4Cl soln, water and brine, dried over MgSO4
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-964086931cb546acacf53510dfb27e2e
Source dataset
uspto-grants-2003_04
Patent number
US06541505B1

Reaction notes

Loading…