METHYL 2-AMINO-4,5,6,7-TETRAHYDROTHIENO[2,3-C]PYRIDINE-3-CARBOXYLATE HCL synthesis

Yield:1049767-69-2 47%

Reaction Conditions:

with sulfur;diethylamine in methanol at 20; for 5 h;

Steps:

I.2.a'

Synthesis of 2-Amino-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine-3-carboxylic acid methyl ester hydrochloride (17)Piperidone-(4), hydrochloride (15, 154 g, 1.1 mol), Methyl-cyanacetat (16, 84 g, 0.8 mol) and sulfur (32 g, 1 mol) were suspended in 500 ml methanol. Then diethyl amine (150 ml, 1.4 mol) was added. The mixture was stirred at room temperature for 5 h. The resulting crystals were filtered, washed with a mixture of iso-propanol and methanol and dried. The mother liquor was reduced to 50 % volume in vacuo and left over night. The resulting crystals were again filtered, washed with iso- propanol and dried. In total 133 g of the desired product 17 (0.54 mol, 47%) were isolated, characterized by NMR and further used in reactions in analogy to 12.

References:

WO2010/112124,2010,A1 Location in patent:Page/Page column 66