Benzene → HCID 19041740, compound

HRID 1684031Notes

Reaction equation

HRID 1684031 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:12]([SH:15])[CH2:13][SH:14])[CH:6]=[C:7]([O:10][CH3:11])[C:8]=1[OH:9].[CH3:16][O:17][C:18]1[CH:19]=[C:20]([CH:23]=[C:24]([O:28][CH3:29])[C:25]=1[O:26][CH3:27])[CH:21]=O.C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1.C1C=CC=CC=1>C1C=CC=CC=1.O>[CH3:29][O:28][C:24]1[CH:23]=[C:20]([CH:21]2[S:15][CH:12]([C:5]3[CH:6]=[C:7]([O:10][CH3:11])[C:8]([OH:9])=[C:3]([O:2][CH3:1])[CH:4]=3)[CH2:13][S:14]2)[CH:19]=[C:18]([O:17][CH3:16])[C:25]=1[O:26][CH3:27]

Participants

6

Reactant 4

HCID 241BenzeneHCID 68583,4,5-TrimethoxybenzaldehydeHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)HCID 19041797HCID 19041797, compound

Product 1

HCID 19041740HCID 19041740, compound

Reagents, catalysts & solvents 1

HCID 22272175Benzene--water (1/1)Solvent

Procedure

1-(3,5-dimethoxy-4-hydroxyphenyl)-1,2-ethanedithiol (40) (2.10 g, 8.54 mmole), 3,4,5-trimethoxybenzaldehyde (24) (1.28 g, 6.57 mmole) and 0.857 g of pyridinium paratoluene sulfonate are added to 60 ml dry benzene and refluxed with Dean-Stark removal of the benzene-water azeotrope overnight. The benzene is removed in vacuo, and the remaining oil is extracted into 10% NaOH which was washed with diethylether. The basic layer is reacidified with 10% HCl and the desired product is extracted into ethyl acetate. The organic layer is dried over MgSO4, filtered, and evaporated in vacuo to an oil which is purified by flash column chromatography with 2:1 hex/ethyl acetate as eluent. The product mixture contains a 1.0/1.2 cis/trans ratio after the first recrystallization (1.287 g, 59%). The trans isomer is isolated after six additional recrystallizations from methanol.

Workup

  1. customThe benzene is removed in vacuo
  2. extractionthe remaining oil is extracted into 10% NaOH which
  3. washwas washed with diethylether
  4. extractionthe desired product is extracted into ethyl acetate
  5. dry with materialThe organic layer is dried over MgSO4
  6. filtrationfiltered
  7. customevaporated in vacuo to an oil which
  8. customis purified by flash column chromatography with 2:1 hex/ethyl acetate as eluent
  9. customafter the first recrystallization (1.287 g, 59%)
  10. customThe trans isomer is isolated
  11. customafter six additional recrystallizations from methanol

Sources & evidence

ORD record
ord-b400f77a73ab420cba09150fab9e0cb5
Source dataset
uspto-grants-1997_06
Patent number
US05639782

Reaction notes

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