ChemicalBook CAS DataBase List 5,6-DIHYDRO-4H-CYCLOPENTATHIAZOL-2-YLAMINE

5,6-DIHYDRO-4H-CYCLOPENTATHIAZOL-2-YLAMINE synthesis

7synthesis methods

Product Name:5,6-DIHYDRO-4H-CYCLOPENTATHIAZOL-2-YLAMINE
CAS Number:53051-97-1
Molecular formula:C6H8N2S
Molecular Weight:140.21

2-Amino-5,6-dihydro-4H-cyclopentathiazole hydrochloride

82514-58-7
42 suppliers
$28.60/250mg

5,6-DIHYDRO-4H-CYCLOPENTATHIAZOL-2-YLAMINE

53051-97-1
78 suppliers
$65.00/100mg

Yield:53051-97-1 85%

Reaction Conditions:

with sodium hydrogencarbonate in tetrahydrofuran;water;ethyl acetate at 20; for 0.25 h;

Steps:

4

Example 4; 5,6-Dihydro-4H-cyclopentathiazol-2-ylamine (2), free base: The hydrochloride salt of 2 (16.5 g, 93 mmol) (for synthesis of HCl salt, see, e.g., Erlenmeyer and Scheonauer, Helv. Chim. Acta, vol. 24, p. 172E and 175 (1941) and Huenig et al., Chem. Ber., vol. 93, p. 1518-1525 (1960)) was added to a mixture of aqueous sodium bicarbonate (16.5 g, 250 mL) and 25% THF/EtOAc (160 mL, v/v). The mixture was stirred at room temperature for 15 min. The mixture was clarified by filtration through a pad of celite. The organic layer was separated, dried (MgSO₄), and concentrated in vacuo to 47 g. Toluene (100 mL) was added and the mixture was concentrated in vacuo to 45 g. The mixture was diluted with heptane (40 mL), cooled, and the product was collected by filtration and dried to give the title compound as the free base (10.75 g, 85%). ¹H NMR (CD₃OD) δ 4.88 (2H, s), 2.75-2.70 (2H, m), 2.60-2.55 (2H, m), 2.39-2.33 (2H, m).

References:

US2007/149499,2007,A1 Location in patent:Page/Page column 19