A Gallium(I) β‐Amido‐Imino‐Phosphorane: A Five‐Membered N‐Heterocyclic Gallylene with Enhanced Nucleophilicity

Carbene analogs, especially of the group 13 elements, are interesting synthetic targets as they offer electronic characteristics that differ significantly from N‐heterocyclic carbenes (NHCs). However, in contrast to their parent carbon relatives, NHC analogs of boron, aluminum, and gallium remain rare. Here, the synthesis of a new five‐membered N‐heterocyclic gallylene ( 5 ) is reported. It is based on a novel monoanionic N , N ′‐chelating ligand, that is, a β‐amino‐imino‐phosphorane (BAIP), which features increased electron‐donating capabilities and provides valuable 1 H and 31 P NMR probes for reaction monitoring. 5 is equipped with increased reactivity compared to previous N‐heterocyclic gallylenes as illustrated in the facile oxidative addition of C‐I and even challenging C‐F bonds, which do not require the application of an external Lewis base. Computations provide a rationale for the increased reactivity, which is due to the increased nucleophilicity that results from a high energetic HOMO.