Nitrogen → 4,4'-Tolan-dicarboxylic acid di-tert.-butyl ester

HRID 974209Notes

Reaction equation

HRID 974209 reaction equation
[C:1]([O:5][C:6](=[O:14])[C:7]1[CH:12]=[CH:11][C:10](Br)=[CH:9][CH:8]=1)([CH3:4])([CH3:3])[CH3:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N#N.[C:36]([O:40][C:41](=[O:50])[C:42]1[CH:47]=[CH:46][C:45]([C:48]#[CH:49])=[CH:44][CH:43]=1)([CH3:39])([CH3:38])[CH3:37]>C(#N)C.[Cu]I.CCN(CC)CC>[C:1]([O:5][C:6]([C:7]1[CH:12]=[CH:11][C:10]([C:49]#[C:48][C:45]2[CH:46]=[CH:47][C:42]([C:41]([O:40][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:50])=[CH:43][CH:44]=2)=[CH:9][CH:8]=1)=[O:14])([CH3:4])([CH3:3])[CH3:2]

Participants

8

Reactant 4

HCID 947NitrogenHCID 11776TriphenylphosphineHCID 11334366Tert-butyl 4-bromobenzoateHCID 13965008Tert-butyl 4-ethynylbenzoate

Product 1

HCID 148475264,4'-Tolan-dicarboxylic acid di-tert.-butyl ester

Reagents, catalysts & solvents 3

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 6342AcetonitrileSolvent2×HCID 8471TriethylamineSolvent

Procedure

4-Bromo-benzoic acid tert.-butyl ester, 5.1 g of triphenylphosphine and 375 ml of NEt3 are introduced into 1 l of absolute acetonitrile under nitrogen and N2 is passed through the solution for 20 minutes. 10.5 g of (Pφ3)2PdCl2 and 1.5 g of copper(I)iodide are then added and 166.5 g of 4-ethinyl-benzoic acid tert.-butyl ester dissolved in 1 l of absolute acetonitrile are slowly added dropwise under reflux and the reaction mixture is stirred overnight. The resulting reaction mixture is then suction filtered after cooling, stirred up in water, again suction filtered, dissolved in CH2Cl2 and filtered after the addition of a small quantity of Tonsil, and the solvent is then evaporated off under vacuum. 225 g of 4,4'-Tolan-dicarboxylic acid-di-tert.-butyl ester are obtained.

Workup

  1. additionare slowly added dropwise
  2. temperatureunder reflux
  3. customThe resulting reaction mixture
  4. filtrationsuction filtered
  5. temperatureafter cooling
  6. stirringstirred up in water
  7. filtrationagain suction filtered
  8. dissolutiondissolved in CH2Cl2
  9. filtrationfiltered
  10. additionafter the addition of a small quantity of Tonsil
  11. customthe solvent is then evaporated off under vacuum

Sources & evidence

ORD record
ord-8b63aad949984d1eb9e3fd6260dad1c3
Source dataset
uspto-grants-1991_11
Patent number
US05068300

Reaction notes

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