Pempidine → Ethyl 1-naphthylpropiolate

HRID 2373106Notes

Reaction equation

HRID 2373106 reaction equation
[C:1]([C:3]1[C:12]2[C:7](=[CH:8][CH:9]=[CH:10][CH:11]=2)[CH:6]=[CH:5][CH:4]=1)#[CH:2].CN1C(C)(C)CCCC1(C)C.Cl[C:25]([O:27][CH2:28][CH3:29])=[O:26]>CN(C)C1C=CN=CC=1.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.C(#N)C>[C:3]1([C:1]#[C:2][C:25]([O:27][CH2:28][CH3:29])=[O:26])[C:12]2[C:7](=[CH:8][CH:9]=[CH:10][CH:11]=2)[CH:6]=[CH:5][CH:4]=1

Participants

7

Reactant 3

HCID 6603PempidineHCID 10928Ethyl chloroformateHCID 1233571-Ethynylnaphthalene

Product 1

HCID 13193568Ethyl 1-naphthylpropiolateYield 36%

Reagents, catalysts & solvents 3

HCID 142844-(Dimethylamino)pyridineCatalystHCID 178418397HCID 178418397, compoundCatalystHCID 6342AcetonitrileSolvent

Procedure

First, ethyl 1-naphthylpropiolate was prepared. A mixture of 1-ethynylnaphthalene (7.7 g, 50.6 mmol), 4-(dimethylamino)pyridine (0.06 g, 0.5 mmol), 1,2,2,6,6-pentamethylpiperidine (8.8 g, 55.7 mmol), and acetonitrile (120 mL) was sparged with nitrogen for 10 min, and then tetrakis(triphenylphosphine)palladium(0) (1.3 g, 1.1 mmol) was added. The mixture was sparged with nitrogen for 10 min, heated to reflux, treated dropwise with ethyl chloroformate (12.1 g, 111.3 mmol), and held at reflux for 2 h. The reaction mixture was cooled to ambient and diluted with ligroin. The solution was washed three times with water and then with brine, dried (Na2SO4), and concentrated to deposit a brown oil. The crude product was purified by column chromatography to provide 4.0 g (36% of theory) of ethyl 1-naphthylpropiolate. 1H NMR (CDCl3): δ 1.40 (t, 3H), 4.33 (q, 2H), 7.50 (m, 3H), 7.90 (m, 3H), 8.30 (d, 1H).

Workup

  1. customFirst, ethyl 1-naphthylpropiolate was prepared
  2. customwas sparged with nitrogen for 10 min
  3. customThe mixture was sparged with nitrogen for 10 min
  4. temperatureheated
  5. temperatureto reflux
  6. temperatureat reflux for 2 h
  7. temperatureThe reaction mixture was cooled to ambient and
  8. washThe solution was washed three times with water
  9. dry with materialwith brine, dried (Na2SO4)
  10. concentrationconcentrated
  11. customThe crude product was purified by column chromatography

Sources & evidence

ORD record
ord-7d7baf9b9b4d48e8b44aa9db32d7bd5f
Source dataset
uspto-grants-2008_12
Patent number
US07459263B2

Reaction notes

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