Toluene → 2-(Benzo[b]thiophen-5-yl)-1,3-dioxolane

HRID 979589Notes

Reaction equation

HRID 979589 reaction equation
[CH:1]([C:3]1[CH:11]=[CH:10][C:6]2[S:7][CH:8]=[CH:9][C:5]=2[CH:4]=1)=[O:2].[C:12]1([CH3:18])C=CC=CC=1.C1(C)C=CC(S(O)(=O)=[O:26])=CC=1>C(O)CO>[O:2]1[CH2:18][CH2:12][O:26][CH:1]1[C:3]1[CH:11]=[CH:10][C:6]2[S:7][CH:8]=[CH:9][C:5]=2[CH:4]=1

Participants

5

Reactant 3

HCID 1140TolueneHCID 6101p-Toluenesulfonic acidHCID 139097Benzo(b)thiophene-5-carboxaldehyde

Product 1

HCID 139229092-(Benzo[b]thiophen-5-yl)-1,3-dioxolaneYield 79%

Reagents, catalysts & solvents 1

HCID 174Ethylene GlycolSolvent

Procedure

A solution of product from Step A (16.4 g, 0.1 mol), toluene (300 ml), p-toluenesulfonic acid (1.0 g) and ethylene glycol (20 ml) was heated at reflux with the aid of a Dean-Stark trap. After 6 hours, the organic layer was cooled, washed with saturated Na2CO3. The Na2CO3 layer was extracted with ethyl acetate (2×). The combined organic extracts were dried, filtered and concentrated to dryness. The residue was distilled at 149-153° C. at 0.3 mm Hg to yield 16.4 g (79%) of product.

Workup

  1. temperatureat reflux with the aid of a Dean-Stark trap
  2. temperaturethe organic layer was cooled
  3. washwashed with saturated Na2CO3
  4. extractionThe Na2CO3 layer was extracted with ethyl acetate (2×)
  5. customThe combined organic extracts were dried
  6. filtrationfiltered
  7. concentrationconcentrated to dryness
  8. distillationThe residue was distilled at 149-153° C. at 0.3 mm Hg

Sources & evidence

ORD record
ord-6dd8bf3338014ad48b059176ebb4b3ed
Source dataset
uspto-grants-1987_05
Patent number
US04668697

Reaction notes

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