isopropyl 2-((tert-butoxycarbonyl)amino)acrylate synthesis

Yield:955379-49-4 96%

Reaction Conditions:

with methanesulfonyl chloride;triethylamine in dichloromethane at 0 - 20; for 4 h;

Steps:

1 Step 1 Synthesis of isopropyl 2-((tert-butoxycarbonyl)amino)acrylate H5-1a

To a stirred solution of isopropyl (tert-butoxycarbonyl)serinate (50 g, 202.4 mmol) and TEA (84 ml_, 607 mmol) in DCM (500 ml_) at 0 °C was added methane sulfonyl chloride (23.38 ml_, 303.3 mmol) dropwise and the resultant the reaction mixture was stirred at room temperature for 4 h. The reaction mixture was quenched with ice water (200 ml_) and extracted with DCM (300 ml_). Organic layer was separated, dried over anhydrous Na₂S04 and concentrated under reduced pressure to obtained crude material, which was purified by Biotage-lsolera using silica snap (230-400 mesh) and eluted with (0-10 %) EtOAc in petroleum-ether gradient to afford isopropyl 2-((tert-butoxycarbonyl)amino)acrylate H5-1a as a colourless gum (45g, 96%). ¹H NMR (400MHz, DMSO-d6) d: 8.36 (s, 1 H), 5.60 (s, 1 H), 5.46 (s, 1 H), 5.0 - 4.94 (m, 1 H), 1.42 (s, 9H), 1.24 (d, J= 6.4 Hz, 6H)

References:

WO2020/249970,2020,A1 Location in patent:Page/Page column 73