Dimethyl Sulfoxide → 4-n-butylidene-5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene

HRID 650592Notes

Reaction equation

HRID 650592 reaction equation
[H-].[Na+].[CH3:3][S:4]([CH3:6])=O.O=[C:8]1[C:17]2[CH:16]=[CH:15]S[C:13]=2[CH2:12][CH2:11][CH2:10][CH2:9]1.[Cl-].[NH4+].[CH3:20][CH2:21]OC(C)=O>[Br-].C([P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)CCC.C1COCC1>[CH:8](=[C:17]1[C:16]2[CH:15]=[CH:6][S:4][C:3]=2[CH2:10][CH2:11][CH2:12][CH2:13]1)[CH2:9][CH2:20][CH3:21]

Participants

8

Reactant 5

HCID 679Dimethyl SulfoxideHCID 8857Ethyl AcetateHCID 24758Sodium hydrideHCID 25517Ammonium ChlorideHCID 123415575,6,7,8-tetrahydro-4H-cyclohepta[b]thiophen-4-one

Product 1

HCID 538249004-n-butylidene-5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene

Reagents, catalysts & solvents 2

HCID 159628Butyltriphenylphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
70 °C

Procedure

A mixture of sodium hydride (NaH) (60% in Nujol, 0.69 g) and dimethyl sulfoxide (DMSO) (9 ml) was stirred at 70° C. for 2 hours. After cooling to r.t., THF (6 ml) and n-butyl-triphenylphosphonium bromide (7.26 g) were added thereto. The reaction mixture was stirred at r.t. for 1 hour, and then 4-oxo-5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene (1.44 g) was added. The mixture was stirred at r.t. overnight and poured into a mixture of a saturated aqueous solution of ammonium chloride (NH4Cl) and AcOEt. The separated organic layer was washed with water and brine, and dried over MgSO4, and evaporated. The resulting oil was purified by chromatography on SiO2 (1% AcOEt in n-hexane as eluent). The fractions containing the object compound were combined and evaporated to give 4-n-butylidene-5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene (1.15 g) as an oil.

Workup

  1. temperatureAfter cooling to r.t.
  2. stirringThe reaction mixture was stirred at r.t. for 1 hour
  3. stirringThe mixture was stirred at r.t. overnight
  4. washThe separated organic layer was washed with water and brine
  5. dry with materialdried over MgSO4
  6. customevaporated
  7. customThe resulting oil was purified by chromatography on SiO2 (1% AcOEt in n-hexane as eluent)
  8. additionThe fractions containing the object compound
  9. customevaporated

Sources & evidence

ORD record
ord-41f28946e95b4cf083322c8e06bc109f
Source dataset
uspto-grants-2001_08
Patent number
US06274619B1

Reaction notes

Loading…