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The syntheses and structures of heteroleptic germanium(II) and tin(II) chlorides supported by anionic ligands derived from 2,3-dimethyl-1,4-diaza-1,3-butadiene are described. The reaction of ArN=C(Me)C(Me)=NAr ( L, Ar = 2,6- iPr2C6H3) with MeLi in Et2O, followed by treatment with GeCl2 ·dioxane or SnCl2, afforded [ L1ECl] [ L1 = ArN=C(Me)C(Me)2NAr; E = Ge ( 1), Sn ( 2)]. Moreover, L2Li [ L2 = ArN=C(Me)C(=CH2)NAr] reacted with GeCl2 ·dioxane in Et2O to form [{C(=CH)NAr}{C(Me)=NAr}]2(GeCl)2 ( 3). The byproducts are [{C(CH2)NAr}{C(Me)=NAr}Ge]2 ( 4) and L2H ( 5). Furthermore, the reaction of L with LiN iPr2 in Et2O, followed by treatment with SnCl2, afforded [ L2SnCl] ( 6). Compounds 1- 4 and 6 have been characterized by NMR spectroscopy and X-ray crystallography. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the stannylidenideanion[LSn:]−(L = 2,6-(CHNBut)2C6H3) supported by the 2,6-diiminophenylligand is described. The reaction of the chlorostannylene [LSnCl](2) with excess KC8in diethyl ether at roomtemperature afforded the distannylene [LSn:]2(3). The treatment of 3with 2 equiv of KC8in tetrahydrofuran (THF) resulted in the cleavage of the SnI–SnIbond in 3to afford thepotassium stannylidenide [LSnK·THF] (4). The molecularstructure of compound 4as determined by single-crystalX-ray diffraction analysis shows that the K atom is η5-coordinated to the low-valent tin heterocycle. Moreover, the negativecharge at the Sn atom in compound 4is stabilized byan electron delocalization in the low-valent tin heterocycle. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the digermylenes [LGe-GeL] [L = L(1) (3A), L(2) (3B)] supported by the 2,6-diiminophenyl (L(1)) and 2-imino-5,6-methylenedioxylphenyl (L(2)) ligands are described. Their reactivities toward potassium graphite are also reported. The reaction of [LGeCl] [L = L(1) (2A), L(2) (2B)] with KC(8) in tetrahydrofuran (THF) at room temperature afforded the digermylenes [LGe-GeL] [L = L(1) (3A), L(2) (3B)], which are the first examples of diaryldigermylenes stabilized by o-imino donor(s). The treatment of 3A with 2 equiv of KC(8) in Et(2)O, followed by the addition of excess tetramethylethylenediamine (TMEDA), results in cleavage of the Ge(I)-Ge(I) bond to afford the germylidenide anion [L(1)GeK·TMEDA] (4A). Similarly, the reaction of 3B with excess KC(8) in THF afforded the germylidenide anion [L(2)GeK] (4B). The molecular structures of compounds 4A and 4B as determined by single-crystal X-ray diffraction analysis show that the K atoms are η(1)-coordinated with the low-valent Ge atoms. Moreover, the negative charges at the Ge atoms in compounds 4A and 4B are stabilized by electron delocalization in the germanium heterocycles.