Rapid and Facile Synthesis of Isomaleimides: Dehydration of Maleamic Acids using Methanesulfonyl Chloride
作者:Mitchell P. Croatt、Khyarul Alam、Elvis C. McFee
DOI:10.1055/s-0041-1737414
日期:2022.7
The dehydration of maleamicacids using methanesulfonyl chloride as a dehydrating agent to selectively and rapidly (<15 min) generate isomaleimides is reported. A variety of maleamicacid derivatives produce the corresponding isomaleimides in good to excellent yields. Adaptation of this protocol under flow synthesis allows for similar efficiency and decreased reaction times (13 seconds residence time)
In this work, eleven new spiro-beta-lactams have been prepared using the Staudinger reaction of isomaleimides (1a-d) and carboxylic acids (chloroacetic acid, (-)-menthoxyacetic acid (7) and an oxazolidinone derived acid (10)) in the presence of triphosgene under mild condition. All reactions have been shown to be stereoselective. The new stereogenic centers were assigned by X-ray diffraction.