2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane → HCID 59207331, compound

HRID 2242777Notes

Reaction equation

HRID 2242777 reaction equation
[S:1]1[C:5]([CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][O:12][CH2:13][C:14]2([CH2:18][CH3:19])[CH2:17][O:16][CH2:15]2)=[CH:4][CH:3]=[C:2]1[C:20]1[S:21][CH:22]=[CH:23][CH:24]=1.C([Li])CCC.C(O[B:34]1[O:38][C:37]([CH3:40])([CH3:39])[C:36]([CH3:42])([CH3:41])[O:35]1)(C)C>C1COCC1>[CH2:18]([C:14]1([CH2:13][O:12][CH2:11][CH2:10][CH2:9][CH2:8][CH2:7][CH2:6][C:5]2[S:1][C:2]([C:20]3[S:21][C:22]([B:34]4[O:38][C:37]([CH3:40])([CH3:39])[C:36]([CH3:42])([CH3:41])[O:35]4)=[CH:23][CH:24]=3)=[CH:3][CH:4]=2)[CH2:17][O:16][CH2:15]1)[CH3:19]

Participants

5

Reactant 3

HCID 50177412-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolaneHCID 59207314HCID 59207314, compoundHCID 178418339Butyllithium

Product 1

HCID 59207331HCID 59207331, compoundYield 56.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a stirred solution of 3-(6-[2,2′]bithiophenyl-5-yl-hexyloxymethyl)-3-ethyl-oxetane (6.0 g, 16.46 mmol) in anhydrous THF (100 ml) is added n-butyllithium (2.5 M in hexanes, 7.0 ml, 17.50 mmol) dropwise at −78° C. under nitrogen. After complete addition, the mixture is allowed to warm to room temperature, with stirring, over 2 h, followed by the addition of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (3.26 g, 17.5 mmol). The resultant mixture is stirred overnight at room temperature. The reaction is quenched with sat. aq. NH4Cl, and the reaction mixture is extracted with ethyl acetate (3×100 ml). The combined organic extracts are washed with water, brine, and dried over sodium sulphate. The solvent is removed under reduced pressure and the residue is further purified by column chromatography on silica, eluting with petroleum ether/ethyl acetate (9:1 to 4:1), to give 2-{5′-[6-(3-ethyl-oxetan-3-ylmethoxy)hexyl]-[2,2′]bithiophenyl-5-yl}-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane as a blue oil (4.53 g, 56%). 1H NMR (300 MHz, CDCl3): δ (ppm) 7.49 (d, J=3.6 Hz, 1H, Ar—H), 7.14 (d, J=3.6 Hz, 1H, Ar—H), 7.03 (d, J=3.6 Hz, 1H, Ar—H), 6.66 (d, J=3.6 Hz, 1H, Ar—H), 4.43 (d, J=5.8 Hz, 2H, OCH2), 4.34 (d, J=5.8 Hz, 2H, OCH2), 3.48 (s, 2H, OCH2), 3.42 (t, J=6.6 Hz, 2H, OCH2), 2.76 (t, J=7.5 Hz, 2H, ArCH2), 1.32-1.75 (m, 22H, CH2 and CH3), 0.86 (t, J=7.5 Hz, 3H, CH3); 13C NMR (75 MHz, CDCl3): δ (ppm) 144.8 (quat.), 143.7 (quat.), 137.0 (CH), 133.7 (quat.), 124.0 (CH), 123.1 (CH), 123.0 (CH), 83.1 (quat.), 77.5 (OCH2), 72.4 (OCH2), 70.4 (OCH2), 42.4 (quat.), 30.5 (CH2), 29.1 (CH2), 28.4 (CH2), 27.8 (CH2) 25.8 (CH2), 24.9 (CH3), 8.3 (CH3); MS (m/e): 490 (M+, 16%) □305 (79), 223 (25), 205 (100).

Workup

  1. additionAfter complete addition
  2. customThe reaction is quenched with sat. aq. NH4Cl
  3. extractionthe reaction mixture is extracted with ethyl acetate (3×100 ml)
  4. washThe combined organic extracts are washed with water, brine
  5. dry with materialdried over sodium sulphate
  6. customThe solvent is removed under reduced pressure
  7. customthe residue is further purified by column chromatography on silica
  8. washeluting with petroleum ether/ethyl acetate (9:1 to 4:1)

Sources & evidence

ORD record
ord-4f1c0b9f63dd42ddb368b58c974903e8
Source dataset
uspto-grants-2010_03
Patent number
US07674397B2

Reaction notes

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