Sodium Carbonate → [2,2'-Bithiophene]-5-carboxaldehyde

To a solution of thien-2-ylboronic acid (0.939 g, 7.34 mmol) and Na2CO3 (2.40 g, 22.6 mmol) in water (75 mL) is added p-dioxane (75 mL). This mixture is treated sequentially with 5-carboxy-2-thiophenecarboxaldehyde (1.43 g, 7.48 mmol) and palladium (II) acetate (151 mg, 0.673 mmol) and allowed to stir at ambient temperature for 16 hours. The solvent is evaporated in vacuo. To the residue is added EtOAc (400 mL) and water (300 mL). The aqueous layer is acidified to pH 1 with 1.0N aq. HCl. The aqueous layer is extracted with EtOAc (2×200 mL). The organic extracts are combined, washing with brine (200 mL), 5% aq. Na2S2O3 (200 mL), sat. aq. NaCl (200 mL), drying (Na2SO4), and the solvent evaporation in vacuo affords the title compound.

1. customThe solvent is evaporated in vacuo
2. additionTo the residue is added EtOAc (400 mL) and water (300 mL)
3. extractionThe aqueous layer is extracted with EtOAc (2×200 mL)
4. washwashing with brine (200 mL), 5% aq. Na2S2O3 (200 mL), sat. aq. NaCl (200 mL)
5. dry with materialdrying (Na2SO4)
6. customthe solvent evaporation in vacuo

ORD-Eintrag

ord-e97527c8980b4262893c7b5db2e97ea9

Quelldatensatz

uspto-grants-1999_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05874452