Carbonyl group directed synthesis of 3-boryl-3-substituted alkenyl oxindoles and tetrasubstituted β-borylenones

Transition metal-free carbonyl directed boron-Wittig reaction of α-bis(boryl)carbanions with the corresponding isatins or with the α-keto esters/amides was achieved to access alkenyl oxindoles in good yield and high stereoselectivity. The synthesis of 3,3-substituted alkenyl oxindole boronates and tetrasubstituted β-borylesters and β-borylamides was achieved via a transition metal-free carbonyl-directed boron-Wittig reaction of α-bis(boryl)carbanions, which is difficult to achieve via other known methods.