Tetramethyltin → 5-acetyl-3-(N-allyl-N-n-propylamino)chroman

HRID 37660

Reaction equation

HRID 37660 reaction equation
[CH2:1]([N:4]([CH:8]1[CH2:17][C:16]2[C:11](=[CH:12][CH:13]=[CH:14][C:15]=2OS(C(F)(F)F)(=O)=O)[O:10][CH2:9]1)[CH2:5][CH2:6][CH3:7])[CH:2]=[CH2:3].[Li+].[Cl-].C([C:32]1C=C(C)C=C(C(C)(C)C)[C:33]=1[OH:43])(C)(C)C.C[Sn](C)(C)C>CN(C=O)C.C1COCC1.CCCCCC.Cl[Pd]Cl>[C:33]([C:15]1[CH:14]=[CH:13][CH:12]=[C:11]2[C:16]=1[CH2:17][CH:8]([N:4]([CH2:1][CH:2]=[CH2:3])[CH2:5][CH2:6][CH3:7])[CH2:9][O:10]2)(=[O:43])[CH3:32]

Participants

8

Reactant 4

HCID 11661TetramethyltinHCID 314042,6-Di-tert-butyl-4-methylphenolHCID 433294Lithium ChlorideHCID 190282203-(N-Allyl-N-n-propylamino)-5-trifluoromethane-sulfonyloxychroman

Product 1

HCID 190280895-acetyl-3-(N-allyl-N-n-propylamino)chromanYield 39%

Reagents, catalysts & solvents 3

HCID 24290Palladium ChlorideCatalystHCID 6228DimethylformamideSolventHCID 21883165Tetrahydrofuran hexaneSolvent

Conditions

Temperature
120 °C

Procedure

3 -(N-Allyl-N-n-propylamino)-5 -trifluoromethane sulfonyloxychroman (0.28 g, 0.74 mmol), LiCl (0.097 g, 2.3 mmol), PdCl2 (dppf) (0.031 g, 0.04 retool) and 2.6-di- t-butyl- 4-methylphenol (0,005 g) were dissolved in DMF (5.0 mL) in a three-necked round-bottom flask (50 mL) with a magnetic stirrer. The flask was evacuated, followed by inlet of CO (three times). Tetramethyltin (0.12 mL, 0.89 mmol) was added and then the mixture was stirred under an atmosphere of CO (1 arm) at 120° C. (oilbath temp) for 4 hours. The solvent was evaporated, the residue was partitioned between aqueous NH3 (2M) and CH2Cl2 (3×15 mL) and the organic phases were dried (Na2SO4), filtered and concentrated in vacuo. Column chromatography on silica with THF-n-hexane (1:9) as eluent afforded 5-acetyl-3-(N-allyl-N-n-propylamino)chroman (0.078 g, 39% yield) as an oil. The base was precipitated from an ether solution by adding a slight excess of HCl (approx. 3M in ether). The crude salt was collected and dried in vacuo at 40° C. to give a white amorphous powder. Mp 125°-127° C. PdCl 2 (dppf)=dichloro[1,1'-bis(diphenylphosphino)-ferrocene] palladium (II).

Workup

  1. customThe flask was evacuated
  2. customfollowed by inlet of CO (three times)
  3. customThe solvent was evaporated
  4. customthe residue was partitioned between aqueous NH3 (2M) and CH2Cl2 (3×15 mL)
  5. dry with materialthe organic phases were dried (Na2SO4)
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-85f85f5d50794dfab1847d18ddb695c1
Source dataset
uspto-grants-1995_05
Patent number
US05420151

Linked notes

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