4,7-Methano-2H-isoindole-2-propanoic acid, 1,3,3a,4,7,7a-hexahydro-1,3-dioxo-, (3aR,4S,7R,7aS)-rel- synthesis

Yield:200111-36-0 80.2%

Reaction Conditions:

with acetic acid at 80; for 6 h;

Steps:

52 Example 52

(3aR, 4S, 7R, 7aS)-3a,4,7,7a-tetrahydro-4,7-methanoisobenzofuran-1,3-Dione (328 mg, 2.0 mmol) and aminopropionic acid (180 mg, 2.0 mmol) dissolved in 10 mLIn glacial acetic acid, the mixture was heated to 80 ° C for 6 h. The reaction was quenched with water (10 mL).The pH of the solution was adjusted to 6-8 by NaOH solution (0.1 mol/L). Dichloromethane extraction (10mL × 3),Wash with saturated NaHCO3 solution, wash with water, and combine organic phases.Dry over anhydrous sodium sulfate, separate and purify on silica gel column.Made a yellow oil 385mg,LC-MS and 1 H-NMR confirmed the expected intermediate compound in a yield of 80.2%.

References:

CN109867661,2019,A Location in patent:Paragraph 0353; 0355