Germyl reactions with

The Ge-Ge bond can undergo cleavage in reactions with [Bu4N]F to yield metal-free germyl anions, which can be employed in subsequent reactions with alkyl halides (Equation (210), Table 27) and carbonyl species (Equation (211), Table 28).266... 

Transient digermene 86 was postulated as possible intermediate in the reaction of 1,2-dichlorodigermacyclobutane 87 with Mg/MgBr2 in the presence of an alkene, leading to the bicyclic compound 8878 [Eq. (17)]. However, an electron transfer reaction with the intermediate formation of a germyl radical is also a possibility.78 Similarly, transient 1,2-digermacyclobu-... 

We have discussed the direct formation of anions by reaction of silyl- or germyl-lithiums with metal carbonyls (cf. Sect. 2.12) ... 

A range of addition reactions of (TMS)3GeH with alkynes, alkenes, ketones, azines, and quinones has been studied using EPR. In addition, synthetic studies of hydrogermylation of alkynes have shown that the reaction proceeds regio- and stereo-selectively, whereas reactions with alkenes do not take place (presumably owing to the reversibility of the germyl radical addition) (Scheme 29). 

A new method for synthesis of dialkyl peroxides is based on the novel peroxide transfer reaction between Ge or Sn peroxides and alkyl triflates. Mixed diaUcyl peroxides are obtained from the reaction of bis(butyltin)germyl peroxide with alkyl triflates. 

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. 

Germyl copper compounds, obtained in a very low yield by the salt-elimination method42, can be obtained efficiently from the reaction of germyl hydrides with alkoxy... 

A detailed follow-up of the reaction by 13C NMR spectroscopy has shown that the initially formed species is an isomer of 1 with a trans-configuration of the germyl groups with respect to the plane of the cyclohexane ring which exists in the twist-conformation. Over a period of two hours at 25 °C, 85% of the trans-isomer 1 isomerizes into the cis-isomer of 1 and there is no further change in the ratio of the isomers. The crystalline cis-isomer of 1 has been isolated in a pure form and fully characterized. 

It should be noted that tribromogermane forms the product of double germylation Br3GeCH2CH2GeBr3 in its reaction with ethylene even in the absence of ether80. 

A surprising example of a double germylation reaction was first found in the aromatic series. Addition of two GeCl3 groups into 9,10-positions of anthracene and 9-methylantracene (MA) proceeds in the absence of ether, but require bubbling of air through the reaction mixture simultaneously with addition of trichlorogermane81. 

The reactions with germyl iodides were carried out at — 78° with dimethyl ether as solvent. To obtain good yields, the dilithium telluride must be free of ammonia and lithium amides2. 

Methyl trimethylsilyl tellurium and phenyl trimethylsilyl tellurium exchanged the organyltelluro group for halogen in reactions with silyl, germyl, stannyl and plumbyl halides2. 

Acyl silanes753,804 8n and germanes812 can be prepared from MVL (524) or EVL (525) by reaction with silyl and germyl chlorides, respectively, followed by acid hydrolysis (Scheme 143). Vinyl stannanes are useful for the preparation of unsolvated MVL753,754... 

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