N-Heterocyclic carbenes and their heavier homologues are, in part, stabilized by delocalization of the N lone pairs into the vacant p-orbital at carbon (or a heavier Group 14 element center). These interactions are usually absent in the corresponding P-substituted species, owing to the large barrier to planarization of phosphorus. However, judicious selection of the substituents at phosphorus has enabled the synthesis of a diphosphagermylene, [(Dipp)2P]2 Ge, in which one of the P centers is planar (Dipp=2,6-diisopropylphenyl). The planar nature of this P center and the correspondingly short P-Ge distance suggest a significant degree of P-Ge multiple bond character that is due to delocalization of the phosphorus lone pair into the vacant p-orbital at germanium. DFT calculations support this proposition and NBO and AIM analyses are consistent with a Ge-P bond order greater than unity.

Zinc for a minute: The reaction of the alkylzinc bromide [Zn{C(SiMe3)2(SiMe2hpp)}]Br (see structure) with an excess of sodium hydride gives good yields of an unusual zinc hydride cluster, in which five zinc atoms are linked by (μ‐H) bridges, to form a spirocyclic [Zn{(μ‐H)Zn}4(μ‐H)2]4+ array, in which two six‐membered {Zn(μ‐H)}3‐rings are fused at one zinc center.

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The lithiation reaction of 1,3-bis(dimethylaminomethyl)-4,6-dimethyl-2-(trimethylsilylmethyl)benzene 2 with Bu n Li (2 equiv.) affords a unique aggregated species 3 of the parent lithiated compound and Bu n Li in a 2 : 2 ratio in which the bridging carbon atoms and the lithium atoms are arranged in an unprecedented ladder-type arrangement with exclusively bridging alkyl groups.

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