Germanium, substitution

In an analogous reaction utilizing dichlorodiethylgermanium, the corresponding germanium-substituted 1,5-diazocine was obtained.41... 

In addition to the common methods of synthesis, it has been shown that the desulfurization of thioacetals yields organogermanes (Equations (7) and (8)) with excellent selectivity in some cases (Equation (9)).8 Ring-opening reactions of strained [l]ferrocenophanes furnish germanium-substituted ferrocenes9,10 (Equation (10)).9... 

Several new types of Ge-C cleavage reactions have been reported where the departing organic group is a functionalized species. Secondary amines undergo nucleophilic addition to germanium-substituted sulfones to yield sulfolanes... 

Penta-alkylphosphorane intermediates are also inferred from the products of the reaction of these ylides with silacyclobutane, from which hydrogen is eliminated.44 However, the cyclobutane ring is left intact when the reaction is carried out with more bulky ylides (Scheme 10).46 Silicon- and germanium-substituted allenes have been prepared by the reaction of monometallated ketens with stable ylides, e.g. (43).46... 

Goldsmith, J. R. Gallium and germanium substitution in synthetic feldspars. 

Sieber, K.D., Sanches.C.,Turner, J.E. and Somorjai, G. A. (1985) Preparation, characterization and photoelectronic propertiess of germanium-substituted Fe203 single crystals. J. Chem. Soc., Farad. Trans. 81 1263-1274... 

The condensation of benzaldehyde with ethyl cyanoacetate, ethyl malonate and ethyl acetoacetate were carried out with high rates and selectivity promoted by lithium-, sodium, potassium-, and caesium-exchanged X and Y zeolites and on sodium-Germanium substituted faujasite. 

Alkoxy allylic tins, transformations, 9, 353 Alkoxybiphenyl isonitriles, liquid crystals, 12, 277 2-Alkoxy-1,3-butadienes, germanium-substituted, 3, 708 Alkoxycarbenes... 

Silicon and germanium-substituted heterocycles and Si- and Ge-hetero-cycles as anti-tumor agents 87KFZ402. 

Of more synthetic interest is the Cs-X catalyzed liquid phase condensation of benzaldehyde with active methylene compounds such as ethyl cyanoacetate, ethyl malonate and ethyl acetoacetate but the yields in these reactions were only in the 40%-70% region. Higher yields were obtained using a germanium substituted faujasite 2 06 or a nitrided aluminophosphate as the basic catalyst. 

C orma, A Martin-Aranda. RM Sanchez. F. Zeolites as base catalysts condensation of ben/aldchydc derivatives with activated methylcnic compinmds on germanium-substituted IauyjiS e. Journal of Catalysis, 1990 126. 192-198. 

Preparation of a germanium-substituted diazo compound was accomplished by the tosylhydrazone route. On flash vacuum pyrolysis of the diazo compound the major product was germaindane (246). The probable route to its formation involves initial production of the carbene 247 followed by a carbene-to-carbene rearrangement to 248... 

Concepcion-Heydom, R Jia, C. Herein, D. Pfander, N. Karge, H. G. and Jentoft, F. C., Structural and catalytic properties of sodium and cesium exchanged X and Y zeolites, and germanium-substituted X zeolite, Journal of Molecular Catalysis A Chemical 162(1-2), 227-246 (2000). 

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