Sulfuric Acid → HCID 18415047, compound

HRID 1457804Notes

Reaction equation

HRID 1457804 reaction equation
S(=O)(=O)(O)O.C[Si](C)(C)CCOC[O:12][C:13]1[CH:22]=[CH:21][C:20]([O:23]COCC[Si](C)(C)C)=[C:19]2[C:14]=1[CH2:15][O:16][C:17]2=[O:18]>CO>[OH:12][C:13]1[CH:22]=[CH:21][C:20]([OH:23])=[C:19]2[C:14]=1[CH2:15][O:16][C:17]2=[O:18]

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 22100333HCID 22100333, compound

Product 1

HCID 18415047HCID 18415047, compoundYield 98.2%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Conditions

Temperature
23 °C

Procedure

A solution of concentrated sulfuric acid (4.0 mL, 75 mmol, 15 equiv) in dry methanol (50 mL) at 23° C. was added to a solution of 4,7-bis [[2-(trimethylsilyl)ethoxyl]methoxy]phthalide (60, 2.148 g, 5.034 mmol, 1 equiv) in dry methanol (50 mL) at 23° C. The reaction mixture was stirred for 2.0 h at 23° C. The product solution was partitioned carefully between saturated aqueous sodium bicarbonate solution (200 mL), saturated aqueous sodium chloride solution (150 mL), and ethyl acetate (100 mL). The aqueous layer was separated and extracted further with ethyl acetate (2×100 mL). The combined organic layers were dried over sodium sulfate and were concentrated affording the 4,7-dihydroxyphthalide (57) as an off-white solid (821 mg, 98%), which was used without further purification.

Workup

  1. customThe product solution was partitioned carefully between saturated aqueous sodium bicarbonate solution (200 mL), saturated aqueous sodium chloride solution (150 mL), and ethyl acetate (100 mL)
  2. customThe aqueous layer was separated
  3. extractionextracted further with ethyl acetate (2×100 mL)
  4. dry with materialThe combined organic layers were dried over sodium sulfate
  5. concentrationwere concentrated

Sources & evidence

ORD record
ord-77330eae48a2413dbff4ecf0ad72b80b
Source dataset
uspto-grants-1998_12
Patent number
US05849750

Reaction notes

Loading…