Iodine → HCID 14906788, compound

HRID 376082Notes

Reaction equation

HRID 376082 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([P:11](=[O:24])([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:6]=[CH:7][C:8]=1[O:9][CH3:10].C([Li])CCC.CCCCCC.C(NC(C)C)(C)C.C([N-]C(C)C)(C)C.[Li+].[I:51]I>O1CCCC1>[I:51][C:4]1[C:3]([O:2][CH3:1])=[C:8]([O:9][CH3:10])[CH:7]=[CH:6][C:5]=1[P:11](=[O:24])([C:18]1[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1

Participants

8

Reactant 6

HCID 807IodineHCID 7912DiisopropylamineHCID 8058HexaneHCID 2724682Lithium diisopropylamideHCID 14906785HCID 14906785, compound2×HCID 178418339Butyllithium

Product 1

HCID 14906788HCID 14906788, compoundYield 81.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
0 °C

Procedure

db) 3.38 g (10 mmol) of (3,4-dimethoxyphenyl)diphenylphosphine oxide and 50 ml of dry tetrahydrofuran were placed in a 0.3 l four-necked sulphonation flask provided with a stirrer, thermometer, dropping funnel and argon gasification. In a separate Schlenk tube 8.0 ml of 1.6N butyllithium solution in hexane (12.8 mmol) were added dropwise under argon and while stirring at -78° C. to a solution of 1.57 g (15.5 mmol) of diisopropylamine in 10 ml of tetrahydrofuran and the solution was stirred at 0° C. for a further 10 minutes. The thus-prepared lithium diisopropylamide solution was then transferred into the dropping funnel of the reaction apparatus and then added dropwise at about -75° C. to the (3,4-dimethoxyphenyl)-diphenylphosphine oxide solution. The resulting pink suspension was stirred at -78° C. for a further 2 hours. Then, it was treated dropwise at <-70° C. with a solution of 3.3 g (13 mmol) of iodine in 20 ml of tetrahydrofuran. Towards the end of the addition there formed a viscous paste which was difficult to stir and which again dissolved when subsequently left to warm to room temperature. The reaction solution was washed 3 times with 20 ml of saturated Na2S2O3 solution each time and once with saturated NaCl solution, dried over Na2SO4, filtered and evaporated. The residue (5 g) was chromatographed on 200 g of silica gel with ethyl acetate and the resulting product was recrystallized from tert.-butyl methyl ether. There were obtained 3.8 g of (2-iodo-3,4-dimethoxyphenyl)-diphenylphosphine oxide as a light beige crystallizate : m.p. 178.5°-179.5° C.

Workup

  1. customprovided with a stirrer
  2. stirringThe resulting pink suspension was stirred at -78° C. for a further 2 hours
  3. additionTowards the end of the addition
  4. customthere formed a viscous paste which
  5. stirringto stir
  6. dissolutionwhich again dissolved when
  7. waitsubsequently left
  8. temperatureto warm to room temperature
  9. washThe reaction solution was washed 3 times with 20 ml of saturated Na2S2O3 solution each time
  10. dry with materialonce with saturated NaCl solution, dried over Na2SO4
  11. filtrationfiltered
  12. customevaporated
  13. customThe residue (5 g) was chromatographed on 200 g of silica gel with ethyl acetate
  14. customthe resulting product was recrystallized from tert.-butyl methyl ether

Sources & evidence

ORD record
ord-843878903d3d4bada3139ffaace84a34
Source dataset
uspto-grants-1996_01
Patent number
US05488172

Reaction notes

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