Hydrazine hydrate (1:1) → 2-amino-7-aminomethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-3-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 2-amino-7-(1,3-dioxo-1,3-dihydro-isoindol-2-ylmethyl)-4,7-dihydro-5H-thieno[2,3-c]pyran-3-carboxylic acid tert-butyl ester (6.0 g, 0.014 mol) in ethanol (100 ml) was added hydrazine-hydrate (1.4 ml, 0.029 mol). The mixture was stirred at reflux temperature for 1 h. The cooled reaction mixture was filtered and the solvent evaporated in vacuo. The residue was dissolved in diethyl ether (200 ml) and washed with water (100 ml), brine (100 ml), dried (Na2SO4), filtered and the solvent evaporated in vacuo affording 2.9 g (71%) of 2-amino-7-aminomethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-3-carboxylic acid tert-butyl ester as an oil.

Provenance & Evidence