Benzene → 4,4-Dimethylthiochroman

HRID 6533

Reaction equation

HRID 6533 reaction equation
C1([CH:7]([S:12]C(C2C=CC=CC=2)C=C(C)C)[CH:8]=[C:9]([CH3:11])[CH3:10])C=CC=CC=1.O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O.P(=O)(O)(O)O.[CH:43]1[CH:48]=[CH:47][CH:46]=[CH:45][CH:44]=1>>[CH3:10][C:9]1([CH3:11])[C:48]2[C:43](=[CH:44][CH:45]=[CH:46][CH:47]=2)[S:12][CH2:7][CH2:8]1

Participants

5

Reactant 4

HCID 241BenzeneHCID 1004Phosphoric AcidHCID 14812Phosphorus oxide (P4O10)HCID 54518102Phenyl-3-methylbut-2-enylsulfide2×

Product 1

HCID 110194304,4-Dimethylthiochroman

Procedure

To a solution of 15.48g (86.824 mmol) of phenyl-3-methylbut-2-enylsulfide (Compound 60) in 160ml benzene were added successively 12.6g (88.767mmol) of phosphorus pentoxide and 11 ml of 85% phosphoric acid. This solution was refluxed with vigorous stirring under argon for 20 hours, then cooled to room temperature. The supernatant organic layer was decanted and the syrupy residue extracted with 3×50ml ether. Organic fractions were combined and washed with water, saturated NaHCO3 and saturated NaCl solutions and then dried (MgSO4). Solvent was removed in vacuo and the residue purified by kugelrohr distillation (80 degrees C., 0.5mm) to give the title compound as a pale yellow oil. PMR (CDCl3) :& 1.30 (6H, s), 1.90-1.95 (2H, m), 2.95-3.00 (2H, m), 6.96-7.00 (2H, m), 7.04-7.07 (1H, m), 7.30-7.33 (1H, m).

Workup

  1. temperatureThis solution was refluxed
  2. customThe supernatant organic layer was decanted
  3. extractionthe syrupy residue extracted with 3×50ml ether
  4. washwashed with water, saturated NaHCO3 and saturated NaCl solutions
  5. dry with materialdried (MgSO4)
  6. customSolvent was removed in vacuo
  7. distillationthe residue purified by kugelrohr distillation (80 degrees C., 0.5mm)

Sources & evidence

ORD record
ord-906733f298d349598a10f27ec82e8d53
Source dataset
uspto-grants-1993_09
Patent number
US05248777

Linked notes

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