Diastereodivergent Synthesis of 3‐Spirocyclopropyl‐2‐oxindoles through Direct Enantioselective Cyclopropanation of Oxindoles

Falling like dominos: The first direct organocatalytic asymmetric cyclopropanation reaction of oxindole was developed, in which oxindoles were employed as a dinucleophilic C1 synthon and bromonitroolefins with a dielectrophilic center were used as a C2 synthon (see scheme). An amino acid based multifunctional catalyst promoted the 2+1 reaction, giving the products in high yields and excellent enantioselectivities. A divergent synthesis of different stereoisomers of 3-spirocyclopropyl-2-oxindoles was achieved. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.