A Strained Intramolecular P/Al-FLP and its Reactivity toward Allene

FLPs featuring aluminum-phosphane interactions, spring-loaded by a rigid biphenylene linker, have been accessed through a route where trimethyltin units at phosphane-functionalized organic backbones are exchanged by an AlCl2 moiety. The latter is saturated through the interaction with the phosphane donors sufficiently to allow for the isolation of the compounds in monomeric form but upon contact with substrates like CO2 these are readily bound by the Al/P site with release of strain. The system could also be utilized for a unique reactivity, namely the activation of allene, which has not been described in FLP chemistry so far.