(Trifluoromethyl)trimethylsilane → (2R,3R)-3-(tert-Butyl-dimethylsilanyloxy)-2-[(1R)-(2,2,2-trifluoro-1-hydroxyethyl)]pyrrolidine-1-carboxylic acid tert-butyl ester

HRID 751138

Reaction equation

HRID 751138 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][C@@H:10]([O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])[C@H:9]1[CH:21]=[O:22])=[O:7])([CH3:4])([CH3:3])[CH3:2].C[Si](C)(C)[C:25]([F:28])([F:27])[F:26]>[F-].[Cs+].Cl>[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][C@@H:10]([O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])[C@H:9]1[C@@H:21]([OH:22])[C:25]([F:28])([F:27])[F:26])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

5

Reactant 2

HCID 552549(Trifluoromethyl)trimethylsilaneHCID 16732142tert-Butyl-(2S,3R)-3-{[tert-butyl(dimethyl)silyl]oxy}-2-formylpyrrolidine-1-carboxylate

Product 1

HCID 16732286(2R,3R)-3-(tert-Butyl-dimethylsilanyloxy)-2-[(1R)-(2,2,2-trifluoro-1-hydroxyethyl)]pyrrolidine-1-carboxylic acid tert-butyl esterYield 46.7%

Reagents, catalysts & solvents 2

HCID 25953Cesium fluorideCatalystHCID 313Hydrochloric AcidSolvent

Procedure

To aldehyde 51C (2.10 g, 6.38 mmol) was added trimethyl(trifluoromethyl)silane (800 μL, 6.57 mmol) and cesium fluoride (dried under high vacuum at 130° C. for 12 h) (10.0 mg, 0.0658 mmol). The reaction was stirred at rt for 24 h then heated to 50° C. for 5 h. After cooling to rt, 4 N HCl (ca. 10 mL) was added and the reaction was stirred overnight. The brown aqueous solution was decanted and the waxy yellow solid was dried under high vacuum overnight then recrystallized from hexane to provide (2R,3R)-3-(tert-butyl-dimethyl-silanyloxy)-2-[(1R)-(2,2,2-trifluoro-1-hydroxy-ethyl)]-pyrrolidine-1-carboxylic acid tert-butyl ester (66A) (1.19 g) as a white solid. The mother liquor was concentrated and purified via flash chromatography eluting with 5-20% ethyl acetate/hexane to provide (2R,3R)-3-(tert-butyl-dimethyl-silanyloxy)-2-[(1S)-(2,2,2-trifluoro-1-hydroxy-ethyl)]-pyrrolidine-1-carboxylic acid tert-butyl ester (66B) (192 mg) as an oil and a mixture of 66A and starting material 51C (306 mg). The latter mixture was recrystallized from hexane to provide additional 66A (100 mg).

Workup

  1. temperaturethen heated to 50° C. for 5 h
  2. temperatureAfter cooling to rt
  3. stirringthe reaction was stirred overnight
  4. customThe brown aqueous solution was decanted
  5. customthe waxy yellow solid was dried under high vacuum overnight
  6. customthen recrystallized from hexane

Sources & evidence

ORD record
ord-1b71b252765b49e8a2d04876bc83d560
Source dataset
uspto-grants-2008_07
Patent number
US07405234B2

Linked notes

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