Asymmetric Organocatalytic 1,6-Conjugate Addition of para- Quinone Methides Using [1,2]-Phospha-Brook Rearrangement.

Pudovik addition/[1,2]-phospha-Brook rearrangement as an efficient tool for generation of anionic nucleophiles is an attractive strategy for the construction of C-C bonds in organic synthesis. Herein, we report organocatalytic 1,6-conjugate addition of para -quinone methides utilizing Pudovik addition/[1,2]-phospha-Brook rearrangement. Chiral guanidine-sulfonamide catalyzed the three-component reaction efficiently, providing biologically active oxindole/biaryl/phosphorus-based structures in high yields with excellent diastereo- and enantioselectivities. A possible bifunctional catalytic mode was proposed to elucidate the chiral control of this process.