title: Borophosphonate cages: easily accessible and constitutionally dynamic heterocubane scaffolds.
abstract: A versatile and experimentally facile procedure for the synthesis of borophosphonate cages of the general formula [tBuPO(3)BR'](4) is described. The method involves heating of tert-butylphosphonic acid with a boronic acid in toluene to give borophosphonates in [4+4] condensation reactions. The products display a heterocubane structure with bent P-O-B bridges as evidenced by crystallographic analyses. Scrambling experiments show that the borophosphonate cages are constitutionally dynamic scaffolds with exchange reactions occurring on the hour time scale at room temperature. The cages can be decorated with reactive groups such as aldehydes. Our results demonstrate that borophosphonate cages are interesting building blocks for dynamic covalent chemistry.
authors: Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors: Justus
authors: J
authors: Tönnemann
authors: Rosario
authors: R
authors: Scopelliti
authors: Konstantin O
authors: KO
authors: Zhurov
authors: Laure
authors: L
authors: Menin
authors: Stefanie
authors: S
authors: Dehnen
authors: Kay
authors: K
authors: Severin