N-Heterocyclic carbenes are shown to cleanly abstract dihydrogen from organotin di- and trihydrides to intermediately form the reactive stannylene species [R2Sn] and [R′SnH], respectively, which undergo further reactions.

Although hydrides of the group 14 elements are well-known as versatile starting materials in many chemical transformations, a hydride of lead in oxidation state II is so far unknown. In this work, we finally complete the jigsaw puzzle by reporting the isolation of the first low valent organolead hydride. The thermolabile dimeric organolead hydride was synthesized at low temperature and features a hydride H NMR signal (in solution 35.61 ppm; in the solid state 31.1 ppm) at the lowest field observed so far for a diamagnetic compound in agreement with quantum chemical predictions.

Amine bases are shown to induce reductive elimination of dihydrogen from terphenyltin trihydride.

An efficient transition-metal-free amination of benzoxazoles has been developed. With catalytic amounts of tetrabutylammoniumiodide (TBAI), aqueous solutions of H(2)O(2) or TBHP as co-oxidant and under mild reaction conditions, highly desirable 2-aminobenzoxazoles were isolated in excellent yields of up to 93%. First mechanistic experiments indicate the in situ iodination of the secondary amine as the putative mode of activation.

Intramolecular germylene, stannylene, and plumbylene Lewis pairs were reacted with hexanal and yielded the cyclic addition products only with the germanium and tin reagents. In further reactivity studies, the hydroboration of aldehydes and ketones catalyzed by intramolecular germylene, stannylene, and plumbylene Lewis pairs was studied. In the case of the cyclic germylene Lewis pair, the product of the oxidative addition of pinacolborane at the germylene moiety was observed. According to stoichiometric as well as catalytic experiments, the intramolecular germylene Lewis pair acts as a catalyst in the hydroboration of aldehydes and ketones. The homologous stannylene Lewis pair forms a reactive tin hydride during the catalysis, which can also act as a catalyst in this transformation.

Hydrogen can be selectively removed from organotin trihydrides to generate the corresponding organohydrostannylene intermediates. Depending on the size of the substituent and the mode of generation, the intermediates undergo further reactions. Herein, we report on the formation of a variety of organotin hydrides with tin in the oxidation states Sn(II) , Sn(I) -Sn(III) and Sn(III) -Sn(III) , all accessed by the controlled removal of hydrogen from the tetravalent Ar'Sn(IV) trihydride (Ar'=2,6-dimesitylphenyl, mesityl=2,4,6-trimethylphenyl).

The weakly coordinating anion [Me3 NB12 Cl11 ](-) has been prepared by a simple two-step procedure. The anion [Me3 NB12 Cl11 ](-) is easily obtained in batches of up to 20 g by chlorination of the known [H3 NB12 H11 ](-) anion with SbCl5 at about 190 °C and subsequent N-methylation with methyl iodide. Starting from Na[Me3 NB12 Cl11 ], several synthetically useful salts with reactive cations ([NO](+) , [Ph3 C](+) , and [(Et3 Si)2 H](+) ) were prepared. Full spectroscopic (NMR, IR, Raman, TGA, MS) characterization and single-crystal X-ray diffraction studies confirmed the identity and purity of the products. The thermal, chemical, and electrochemical stability as well as the basicity of the [Me3 NB12 Cl11 ](-) anion is similar to that of the structurally related weakly coordinating 1-carba-closo-dodecaborate and closo-dodecaborate anions. The facile preparation of the [Me3 NB12 Cl11 ](-) anion and its ideal chemical and physical properties make it a cheap alternative to other classes of weakly coordinating anions.

Tetrylidynes [(Me3P)2(Ph3P)Rh≡SnAr*] (10) and [(Me3P)2(Ph3P)Rh≡PbAr*] (11) are accessed for the first time via dehydrogenation of dihydrides [(Ph3P)2RhH2SnAr*] (3) and [(Ph3P)2RhH2PbAr*] (7) (Ar*=2,6‐Trip2C6H3, Trip=2,4,6‐triisopropylphenyl), respectively. Tin dihydride 3 was either synthesized in reaction of the dihydridostannate [Ar*SnH2]− with [(Ph3P)3RhCl] or via reaction between hydrides [(Ph3P)3RhH] and 1/2  [(Ar*SnH)2]. Homologous lead hydride [(Ph3P)2RhH2PbAr*] (7) was synthesized analogously from [(Ph3P)3RhH] and 1/2  [(Ar*PbH)2]. Abstraction of hydrogen from 3 and 7 supported by styrene and trimethylphosphine addition yields tetrylidynes 10 and 11. Stannylidyne 10 was also characterized by 119Sn Mössbauer spectroscopy. Hydrogenation of the triple bonds at room temperature with excess H2 gives the cis‐dihydride [(Me3P)2(Ph3P)RhH2PbAr*] (12) and the tetrahydride [(Me3P)2(Ph3P)RhH2SnH2Ar*] (14). Complex 14 eliminates spontaneously one equivalent of hydrogen at room temperature to give the dihydride [(Me3P)2(Ph3P)RhH2SnAr*] (13). Hydrogen addition and elimination at stannylene tin between complexes 13 and 14 is a reversible reaction at room temperature.