1,3-Carboboration of iodonium ylides.

Herein, we disclose the utilisation of iodonium ylides to access a range of boron dienolates. Heating of acyclic iodonium ylides in the presence of different aryl boranes leads to the formation of rare 1,3-carboboration products. This methodology could not be expanded to cyclic iodonium ylides which instead formed a Lewis acid-base adduct. Products proved to be remarkably stable under a wide range of conditions allowing for their long term storage.