Triethylamine → 5-Methyl-3-(3,3,3-trifluoro-2-methoxy-2-phenyl-propionyl oxymethyl)-2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid methyl ester

HRID 968948

Reaction equation

HRID 968948 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:16]=[CH:15][C:8]2[O:9][CH2:10][CH:11]([CH2:13][OH:14])[O:12][C:7]=2[C:6]=1[CH3:17])=[O:4].C(N(CC)CC)C.[CH3:25][O:26][C@:27]([C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=1)([C:31]([F:34])([F:33])[F:32])[C:28](Cl)=[O:29]>C(Cl)Cl>[CH3:1][O:2][C:3]([C:5]1[CH:16]=[CH:15][C:8]2[O:9][CH2:10][CH:11]([CH2:13][O:14][C:28](=[O:29])[C:27]([O:26][CH3:25])([C:35]3[CH:36]=[CH:37][CH:38]=[CH:39][CH:40]=3)[C:31]([F:33])([F:34])[F:32])[O:12][C:7]=2[C:6]=1[CH3:17])=[O:4]

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 3080792(-)-alpha-Methoxy-alpha-(trifluoromethyl)phenylacetyl chloride2×HCID 687788313-Hydroxymethyl-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid methyl ester

Product 1

HCID 687829545-Methyl-3-(3,3,3-trifluoro-2-methoxy-2-phenyl-propionyl oxymethyl)-2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid methyl ester

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a round bottom flask equipped with magnetic stirring and a nitrogen inlet was added 3-hydroxymethyl-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid methyl ester (0.10 g, 0.44 mmol) and dry methylene chloride (1.5 mL). The mixture was cooled in an ice bath and triethylamine (0.12 mL, 0.87 mmol) was added followed by (R)-(−)-α-methoxy-α-trifluoromethylphenylacetyl chloride (0.09 mL, 0.48 mmol). The mixture was stirred for 2 hours at which point TLC showed the reaction to be incomplete. More (R)-(−)-α-methoxy-α-trifluoromethylphenylacetyl chloride (0.09 mL, 0.48 mmol) was added and the reaction was allowed to stir 1 hour at room temperature. The mixture was diluted with methylene chloride, washed once with 1N HCl, once with saturated sodium bicarbonate, dried over magnesium sulfate, filtered and evaporated. The residue was chromatographed on silica gel eluting with methylene chloride to give a clear oil, 5-methyl-3-(3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxymethyl)-2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid methyl ester, for which a yield was not determined. 1H-NMR (300 MHz, CD3COCD3) δ (ppm): 2.38 (s, 3H), 3.58 (s, 3H), 3.81 (s, 3H), 4.10 (m, 1H), 4.48 (dd, 1H), 4.65 (m, 2H), 4.86 (m, 1H) 6.78 (d, 1H) 7.47 (m, 5H), 7.60 (d, 1H); 19F-NMR (300 MHz, CD3COCD3) δ (ppm): −72.89 (s); both 1H- and 19F-NMR indicate the presence of only one stereo- and regioisomer; TLC: Rf=0.62 (1:1 ethyl acetate/hexane).

Workup

  1. customTo a round bottom flask equipped
  2. temperatureThe mixture was cooled in an ice bath
  3. stirringThe mixture was stirred for 2 hours at which point TLC
  4. customthe reaction
  5. stirringto stir 1 hour at room temperature
  6. washwashed once with 1N HCl, once with saturated sodium bicarbonate
  7. dry with materialdried over magnesium sulfate
  8. filtrationfiltered
  9. customevaporated
  10. customThe residue was chromatographed on silica gel eluting with methylene chloride

Sources & evidence

ORD record
ord-d170cb1684704abeb2d1866c4b9657d8
Source dataset
uspto-grants-2007_12
Patent number
US07304161B2

Linked notes

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