Tetramethoxysilane → 6-Benzyloxy-3-(2-methoxy-5-nitrobenzylidene)-2,2-dimethylchroman-4-one

HRID 1684622Notes

Reaction equation

HRID 1684622 reaction equation
[CH2:1]([O:8][C:9]1[CH:10]=[C:11]2[C:16](=[CH:17][CH:18]=1)[O:15][C:14]([CH3:20])([CH3:19])[CH2:13][C:12]2=[O:21])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[F-].[K+].[CH3:24][O:25][C:26]1[CH:33]=[CH:32][C:31]([N+:34]([O-:36])=[O:35])=[CH:30][C:27]=1[CH:28]=O.CO[Si](OC)(OC)OC>CN(C)C=O.C(OCC)(=O)C.O>[CH2:1]([O:8][C:9]1[CH:10]=[C:11]2[C:16](=[CH:17][CH:18]=1)[O:15][C:14]([CH3:19])([CH3:20])[C:13](=[CH:28][C:27]1[CH:30]=[C:31]([N+:34]([O-:36])=[O:35])[CH:32]=[CH:33][C:26]=1[O:25][CH3:24])[C:12]2=[O:21])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

8

Reactant 4

HCID 12682TetramethoxysilaneHCID 90685Benzaldehyde, 2-methoxy-5-nitro-HCID 522689Potassium FluorideHCID 117809926-Benzyloxy-2,2-dimethylchroman-4-one

Product 1

HCID 539321056-Benzyloxy-3-(2-methoxy-5-nitrobenzylidene)-2,2-dimethylchroman-4-oneYield 79%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
80 °C

Procedure

A mixture of 5.0 g (17.7 mmole) of the product of Example 100, 1.1 g (19 mmol) potassium fluoride, 3.5 g (19.5 mmole) 2-methoxy-5-nitrobenzaldehyde and 2.9 mL (2.97 g, 19.5 mmole) tetramethylortho-silicate in 15 mL dimethylformamide was heated at 80° C. for 7 hours. The mixture was poured into water and extracted with ethyl acetate. The ethyl acetate extract was and washed successively with 1N HCl, 5% NaHCO3, water and brine and then dried (MgSO4) and concentrated to give an oil. Flash chromatography on silica gel eluting with 30% ethyl acetate in hexanes gave 6.23 g (79%) of a foam. Recrystallization from ethyl acetate in hexanes yielded the title product as a solid m.p. 110°-112° C. NMR (CDCl3): δ1.70 (s, 6H); 3.82 (s, 3H); 5.02 (s, 2H). Analysis calculated for C20H23NO6 : C, 70.10; H, 5.20; N, 3.14. Found: C, 70.19; H, 5.21; N, 3.14.

Workup

  1. extractionextracted with ethyl acetate
  2. extractionThe ethyl acetate extract
  3. washwashed successively with 1N HCl, 5% NaHCO3, water and brine
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated
  6. customto give an oil

Sources & evidence

ORD record
ord-b44871cbf0754d78886776c1b67518f5
Source dataset
uspto-grants-1997_06
Patent number
US05641789

Reaction notes

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