α-Cyclodextrin Encapsulation of Bicyclo[1.1.1]pentane Derivatives: a Storable Feedstock for Preparation of [1.1.1]Propellane

The bicyclo[1.1.1]pentane (BCP) scaffold is useful in medicinal chemistry, and many protocols are available for synthesizing BCP derivatives from [1.1.1]propellane. Here, we report (1) the alpha-cyclodextrin (alpha-CD) encapsulation of BCP derivatives, affording a stable, readily storable material from which BCPs can be easily and quantitatively recovered and (2) new and simple protocols for deiodination reaction of 1,3-diiodo BCP to afford [1.1.1]propellane in protic/aprotic/polar/non-polar solvents. The combination of these methodologies enables simple, on-demand preparation of [1.1.1]propellane in various solvents under mild conditions from alpha-CD capsules containing 1,3-diiodo BCP.

Automated summary

The study reports a new method utilizing alpha-cyclodextrin to encapsulate BCP derivatives, enabling their stable storage and recovery. Additionally, a simple method has been developed to obtain [1.1.1]propellane from 1,3-diiodo BCP, and the combination of these methods allows for the rapid preparation of [1.1.1]propellane in various solvents under mild conditions.