Title | Nitrone and Alkyne Cascade Reactions for Regio- and Diastereoselective 1-Pyrroline Synthesis. |
Publication Type | Journal Article |
Year of Publication | 2021 |
Authors | Zhang G, Alshreimi AS, Alonso L, Antar A, Yu H-C, Islam SM, Anderson LL |
Journal | Angew Chem Int Ed Engl |
Volume | 60 |
Issue | 23 |
Pagination | 13089-13097 |
Date Published | 2021 06 01 |
ISSN | 1521-3773 |
Abstract | The synthesis of 1-pyrrolines from N-alkenylnitrones and alkynes has been explored as a retrosynthetic alternative to traditional approaches. These cascade reactions are formal [4+1] cycloadditions that proceed through a proposed dipolar cycloaddition and N-alkenylisoxazoline [3,3']-sigmatropic rearrangement. A variety of cyclic alkynes and terminal alkynes have been shown to undergo the transformation with N-alkenylnitrones under mild conditions to provide the corresponding spirocyclic and densely substituted 1-pyrrolines with high regio- and diastereoselectivity. Mechanistic studies provide insight into the balance of steric and electronic effects that promote the cascade process and control the diastereo- and regioisomeric preferences of the 1-pyrroline products. Diastereoselective derivatization of the 1-pyrrolines prepared by the cascade reaction demonstrate the divergent synthetic utility of the new method. |
DOI | 10.1002/anie.202101511 |
Alternate Journal | Angew Chem Int Ed Engl |
PubMed ID | 33763941 |