Ethyl1-[[(2-chloro-5-nitro-pyrimidin-4-yl)-propan-2-yl-amino]methyl]cyclopropane-1-carboxylate → 2'-chloro-9'-isopropyl-8',9'-dihydrospiro[cyclopropane-1,7'-pyrimido[5,4-b][1,4]diazepin]-6'(5'H)-one

Participants

Reaction Conditions

Reaction Steps

Ethyl1-[[(2-chloro-5-nitro-pyrimidin-4-yl)-propan-2-yl-amino]methyl]cyclopropane-1-carboxylate (Intermediate 208; 10.26 g, 30 mmol) was dissolved in acetic acid (500 mL) and heated to 70° C. Iron powder (6 g) was added in portions over 10 minutes. The mixture was stirred at 70° C. for 3 hours. The reaction mixture was filtered hot through celite, and the pad washed with DCM. The filtrate was evaporated to dryness then sonicated in saturated aqueous sodium hydrogen carbonate solution to give a brown suspension. This was filtered, and the resulting solid washed with water. The solid was then sucked dry on a filter, and suspended in a small amount of methanol with sonication. The methanol suspension was then diluted with DCM (10× excess), and filtered to give a yellow solution, which was dried over sodium sulphate, then concentrated in vacuo to give a yellow/green solid. The solid was triturated under cold methanol to yield the title compound as a white powder. (5 g, 63%)

Provenance & Evidence