Germanium—carbon bonds reactions with

That the carbon—metal or carbon—metalloid bonds are preserved at all in these reactions is quite surprising. With tetramethylgermanes, for example, this free radical reaction must be a 24 step process. The success in preserving carbon-germanium bonds must arise from very rapid molecular vibrational, rotational, and translational relaxation processes occurring on the cryogenically cooled surfaces such that the energy from the extremely exothermic reaction is smoothly dissipated. 

Cycloadditions have also been used to form germanium-carbon bonds at germanium surfaces. For example, 1,3-butadiene and 2,3-dimethyl-1,3-butadiene react with the dimers present on Ge(100)-2xl to form a six-membered ring and two new Ge-C bonds. Reactions with other unsaturated species such as ethylene, ketones, and nitriles have also been explored. ... 

Germanium-carbon bonds can easily be formed in the reaction of organohydrido germanium lithium compounds with organic halides as shown in equation 3541. 

The germabenzene species 15 reacts in two different fashions with a variety of substrates to give cylcoaddition products (Scheme 7).30 With MesCNO and 2,3-dimethylbutadiene, 15 behaves similarly to a compound with a single Ge-C double bond, whereas in reactions with styrene and phenylacetylene, 15 behaves as a 1-germabuta-l,3-diene to give Diels-Alder-type adducts. The germanium-carbon doubly bonded species 23 reacts with nitriles in several different ways, including as a 1,2-dipolar species with Bu CN, as a 1,4-dipolar species with PhCN, and as a base with various /3-functionalized nitriles (Scheme 8). 

Germanium and silicon hydrides should be even more selective toward alkoxyl radicals relative to carbon radicals. Indeed, while silicon hydrides react rapidly with alkoxyl radicals, reactions with carbon radicals are too slow to propagate chains. The rapid addition of silyl and germyl radicals to C—O bonds is a possible complicating reaction. 

Germanium-carbon multiple bonds, formation, 3, 709 Germanium-chalcogen bonds, reactivity, 3, 745 Germanium complexes with alkali metal bonds, 3, 748 with Isis // -arcnc chromium heteroatoms, 5, 340 with chromium carbonyls, 5, 208 coupling reactions, 3, 711 with CpMoCO, 5, 463... 

Inter-ring metal migrations, dynamic NMR studies, 1, 412 Intracyclic germanium-carbon bond formation large rings, 3, 706 small rings, 3, 703 Intramolecular Alder-ene reactions with metals, 10, 576 with palladium, 10, 568 with rhodium, 10, 575 with ruthenium, 10, 572 with transition metal catalysts, 10, 568 Intramolecular allylations, in cyclizations, with indium compounds, 9, 679... 

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