4,4,5,5-Tetramethyl[1,3,2]dioxaborolane → HCID 90412712, compound

HRID 1746639Notes

Reaction equation

HRID 1746639 reaction equation
[C:1]([Si:5]([O:18][C@@H:19]1[C@H:26]2[C@H:22]([O:23][C:24]([CH3:28])([CH3:27])[O:25]2)[C:21]([CH2:29][O:30][C:31]([C:44]2[CH:49]=[CH:48][CH:47]=[CH:46][CH:45]=2)([C:38]2[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=2)[C:32]2[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=2)=[C:20]1I)([C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)([CH3:4])([CH3:3])[CH3:2].[CH3:51][C:52]1([CH3:59])[C:56]([CH3:58])([CH3:57])[O:55][BH:54][O:53]1>C1COCC1>[CH3:28][C:24]1([CH3:27])[O:25][C@H:26]2[C@@H:19]([O:18][Si:5]([C:1]([CH3:2])([CH3:4])[CH3:3])([C:12]3[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=3)[C:6]3[CH:7]=[CH:8][CH:9]=[CH:10][CH:11]=3)[C:20]([B:54]3[O:55][C:56]([CH3:58])([CH3:57])[C:52]([CH3:59])([CH3:51])[O:53]3)=[C:21]([CH2:29][O:30][C:31]([C:32]3[CH:33]=[CH:34][CH:35]=[CH:36][CH:37]=3)([C:38]3[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=3)[C:44]3[CH:49]=[CH:48][CH:47]=[CH:46][CH:45]=3)[C@H:22]2[O:23]1

Participants

4

Reactant 2

HCID 27347684,4,5,5-Tetramethyl[1,3,2]dioxaborolaneHCID 90412667HCID 90412667, compound

Product 1

HCID 90412712HCID 90412712, compoundYield 35%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

To a 25 mL round-bottom 3-neck flask equipped with nitrogen inlet/outlet, stir bar, and thermocouple with temperature controller was charged 0.2806 g of compound 8 (0.353 mmol, 1.0 eq) and 3 mL tetrahydrofuran (10 V). The reaction was cooled to 0° C. To this solution was added 0.653 mL (0.847 mmol, 2.4 eq) of isopropylmagnesium chloride lithium chloride complex, 1.3 M in THF slowly over 15 minutes. The reaction was stirred at 0° C. for 1 hour. HPLC assay indicated formation of intermediate. 0.128 mL of 4,4,5,5 tetramethyl-1,3,2 dioxaborolane (0.884 mmol, 2.5 eq) was added to the reaction. An HPLC assay after 1 hour at 0° C. indicated that the reaction was completed. The reaction was quenched with saturated aqueous ammonium chloride solution (3V). The ice bath was removed and the reaction warmed to room temperature. The reaction was charged with DI water (3V) and ethyl acetate (6V). The layers were separated and the aqueous layer was back-extracted with ethyl acetate (6V). The organic phases were combined and washed with brine (3V) and dried over MgSO4. The resulting mixture was filtered. The filtrate was concentrated to dryness by the rotary evaporator. Obtained 0.098 grams as a white solid, (35% yield), 80 A % purity of [(3aR,6S,6aR)-2,2-dimethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-4-(trityloxymethyl)-6,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-6-yl]oxy-tert-butyl-diphenyl-silane (compound 9c-2).

Workup

  1. customTo a 25 mL round-bottom 3-neck flask equipped with nitrogen inlet/outlet
  2. stirringThe reaction was stirred at 0° C. for 1 hour
  3. customThe reaction was quenched with saturated aqueous ammonium chloride solution (3V)
  4. customThe ice bath was removed
  5. temperaturethe reaction warmed to room temperature
  6. additionThe reaction was charged with DI water (3V) and ethyl acetate (6V)
  7. customThe layers were separated
  8. extractionthe aqueous layer was back-extracted with ethyl acetate (6V)
  9. washwashed with brine (3V)
  10. dry with materialdried over MgSO4
  11. filtrationThe resulting mixture was filtered
  12. concentrationThe filtrate was concentrated to dryness by the rotary evaporator

Sources & evidence

ORD record
ord-eab7e7efb71b43078a7f66c356eab630
Source dataset
uspto-grants-2015_10
Patent number
US09150520B2

Reaction notes

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