ChemicalBook CAS DataBase List 2,3-Dihydro-1-benzofuran-2-carboxylic acid

2,3-Dihydro-1-benzofuran-2-carboxylic acid synthesis

9synthesis methods

Product Name:2,3-Dihydro-1-benzofuran-2-carboxylic acid
CAS Number:1914-60-9
Molecular formula:C9H8O3
Molecular Weight:164.16

496-41-3

2,3-Dihydro-1-benzofuran-2-carboxylic acid

1914-60-9

a) Synthesis of (R,S)-2,3-dihydro-benzofuran-2-carboxylic acid (54a): commercially available benzofuran-2-carboxylic acid (Aldrich Chemical Company, 27 g, 167.7 mmol) was dissolved in ethyl acetate (300 mL). The hydrogenation reaction was catalyzed by 10% Pd/C (20 g) at 65-70 psi hydrogen pressure for 2 days. Upon completion of the reaction, the catalyst was removed by filtration and the solvent was evaporated. A solvent mixture of ethyl acetate-hexane (1:6) was added to the residue for recrystallization. Filtration afforded benzodihydrofuran-2-carboxylic acid as a crystalline solid (20.23 g, 74% yield). Melting point: 116-117 °C. 1H NMR (300 MHz, CDCl3) δ: 11.05 (brs, 1H), 7.17 (m, 2H), 6.91 (m, 2H), 5.24 (dd, 1H), 3.63 (dd, 1H), 3.42 (dd, 1H).

496-41-3
259 suppliers
$6.00/1g

1914-60-9
111 suppliers
$14.00/100mg

Yield: 74%

Reaction Conditions:

with hydrogen;palladium 10% on activated carbon in ethyl acetate under 3361.55 - 3620.13 Torr; for 48 h;

Steps:

54.a
a) (R,S)-2,3-Dihydro-benzofuran-2-carboxylic acid (54a) Commercially available benzofuran-2-carboxylic acid (Aldrich Chemical Company) (27 g, 167.7 mmol) was dissolved in ethyl acetate (300 mL) and hydrogenated in the presence of 10% Pd/C (20 g) at 65-70 psi for 2 days. After filtration of the solution and evaporation of the solvent, a mixture of solvent (ethyl acetate-hexane, 1:6) was added to the residue. The title compound was obtained as a crystalline solid by filtration (20.23 g, 74%). m.p: 116-117° C.; ¹H NMR (300 MHz, CDCl₃) δ: 11.05 (brs, 1H), 7.17 (m, 2H), 6.91 (m, 2H), 5.24 (dd, 1H), 3.63 (dd, 1H), 3.42 (dd, 1H).

References:

Dolle, Roland E.;Chu, Guo-Hua US2005/54630, 2005, A1 Location in patent:Page/Page column 42

66158-96-1 Synthesis