Germylenes complexes

It is interesting to note that no examples are known for a retro-reaction of this dimerization. Such a reaction has been observed, however, for germylene complexes and for stannylene complexes, in some cases an equilibrium between uncomplexed and base-stabilized compounds has been found. 

Whether these results will also have an impact on the theory of metallaallenes is difficult to predict at least for the compounds Cp (CO)2Mn = M = Mn(CO)2Cp, (M = Ge, Sn, Pb) a linear structure is established and also linear p-carbido complexes are known [198], Recently, a germanium compound has been synthesized which is directly comparable with 22. In this case, the starting material for the synthesis is not a monomeric base adduct, but a dimeric germylene complex which is cleaved by Na2Fe(CO)4 in pyridine to form 72 [199],... 

Ogino, Hiroshi, and Tobita, Hiromi, Bridged Silylene and Germylene Complexes. 42 223... 

Diethyl-1,3,2-dithiagermolane (336) reacts with the chromium pentacarbonyl complex of dichlorogermylene (in the form of solvate with THF) to give a cyclic germylene complex (337) which can be further stabilized with an additional nitrone ligand <87JOM(33i)ii>. 

These germylene complexes are light yellow to orange, rather air sensitive but thermostable, crystalline compounds, easily soluble in aprotic polar and nonpolar solvents. According to X-ray investigations, gas phase electron diffraction studies, and molecular weight determinations, the complexes are monomeric species in the solid and gaseous state and also in solution. An... 

B. Synthesis of Bimetallic Bridging Germylene Complexes, LMGeR2ML... 

C. Synthesis of Transition Metal Germanium Double Bond Germylene Complexes... 

The internally stabilized silylamide germylene Ge[N(SiMe3)2]135 reacts with Ni and Pt phosphine complexes yielding Ni136 and Pt-germylene complexes (equation 35)137-139. 

Stable mononuclear transition-metal germylene complexes with a formal triple bond between the Ge and metal atoms (Cr, Mo, W, 56-62) have been synthesized by a combination of salt-elimination and decarbonylation reaction (equation 44)150,151. The decarbonylation process for the Cr and W intermediates 61 and 62 can involve either a thermal or a photochemical reaction the molybdenum germylyne complexes 56 and 57 were obtained directly, even at low temperatures. 

The platinum germylene complex 67 has been extensively studied and an array of interesting chemistry has been developed. The chemistry, outlined in equation 58, is predominantly addition to the M=Ge bond, e.g. to give 68-71. The rearrangement of the 1,2-dioxametallocycle in 68 to the 1,3 isomer 72 is understood in terms of forming two M—O bonds at the expense of the relatively weak 0—0 bond136-139. 

TABLE 9. X-ray structural data of transition metal germylene complexes... 

H. Removal of Carbonyl Ligands from Bridged Germylene Complexes 261... 

IV. Physical Properties of Bridged Silylene and Germylene Complexes. . . 265... 

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