HCID 69029202, compound → HCID 58209852, compound

HRID 1868573Notes

Reaction equation

HRID 1868573 reaction equation
[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:23](=[O:35])[CH2:24][C:25]([C:27]2[CH:32]=[CH:31][C:30]([OH:33])=[CH:29][C:28]=2O)=[O:26])[CH:12]=[C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>CC(O)C>[CH2:16]([O:15][C:13]1[CH:12]=[C:11]([CH:10]=[C:9]([O:8][CH2:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)[CH:14]=1)[C:23]1[O:35][C:32]2[C:27]([C:25](=[O:26])[CH:24]=1)=[CH:28][CH:29]=[C:30]([OH:33])[CH:31]=2)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1

Participants

3

Reactant 1

HCID 69029202HCID 69029202, compound

Product 1

HCID 58209852HCID 58209852, compound

Reagents, catalysts & solvents 1

HCID 3776IsopropanolSolvent

Procedure

A solution of 20% lithiumhexamethyldisilazane in tetrahydrofuran (217.5 mL, 260 mmol) was added to a well-stirred solution of 2,4-dihydroxy acetophenone, 14 (9.88 g, 65 mmol) in tetrahydrofuran (150 mL) under nitrogen atmosphere at −78° C. for 30 min. The reaction mixture was stirred at −78° C. for 1 h and at −30° C. for 2 h. It was again cooled to −78° C. and a solution of ethyl-3,5-dibenzyloxy-benzoate 8 (23.5 g, 65 mmol) in tetrahydrofuran (100 mL) was added over a period of 30 min. It was further stirred at room temperature for overnight and poured into ice water containing hydrochloric acid. It was extracted with chloroform, dried over sodium sulphate, filtered and evaporated on rotavapor to afford 1-(3,5-bis-benzyloxy-phenyl)-3-(2,4-dihydroxy-phenyl)-propane-1,3-dione (16). The residue, 16 (37.8 g) was refluxed with Dowex-H+ (8 g) in 2-propanol (300 mL) for 34 h. 2-Propanol was evaporated on rotavapor, residue suspended in hot dimethyl formamide and filtered. The filtrate was 3,4-Dimethoxy-benzoic acid (10). Yield 2 g (8%); mp 179-181° C.; MS (FAB) 183 (M++1); IR (KBr) 2939, 2836, 1867, 1678; 1H NMR (200 MHz, CDCl3) δ 7.79 (dd, J=8.4 Hz, 1.9 Hz, 1H), 7.60 (d, J=1.8 Hz, 1H), 6.93 (d, J=8.5 Hz, 1H), 3.96 (s, 6H).

Workup

  1. custom2-Propanol was evaporated on rotavapor, residue
  2. filtrationfiltered

Sources & evidence

ORD record
ord-8b2adae12209453f957c90528add0343
Source dataset
uspto-grants-2009_12
Patent number
US07635779B2

Reaction notes

Loading…