Silane/disilane derivatives

These difficulties and generally low yields in the preparation of organic disilane derivatives by the reaction of disilane hexahalide with organometallic compounds lead to the conclusion that the better method for preparation of these compounds is the Wurtz-type synthesis starting from organohalomono-silane. 

The nomenclature of organosilicon compounds is based on the derivatives of silane, disilane, and higher polysilanes. When the silicon group is used as a substituent (silicon-containing radical), silyl, disilanyl, trisilanyl, and polysilanyl are used ... 

Degradation of Larger Silicon Catenates. Although it seems clear that polymeric disilane derivatives photodecompose by bond homolysis to produce silyl radicals, model studies on larger silicon catenates indicate that their photochemistry may be more complex (Scheme IV). Cyclic silane derivatives seem to extrude monomeric silylenes upon irradiation to produce smaller cyclic silanes (52). The proposed silylene intermediates have been identified spectroscopically 49, 53), and trapping adducts have been isolated in solution. Exhaustive irradiation ultimately results in acyclic silanes, which... 

Inverted names are used only for derivatives of silanes (as Silane, dibromo- and Disilane, hexachloro-), germanes, phosphine, and the like, but not for the few organic compounds. For the nomenclature of some of these and other classes of compounds, see the heading Nomenclature. 

In recent years Furstner [15, 16] described the very rapidly and completely conversion of chloro-silanes into disilanes by the help of potassium-graphite (CgK). These coupling reactions were characterized by low temperatures (0-25 C), short reaction times (5-60 min), and high yields (> 90 %). So we tried to reduce our silyltriflate derivatives with potassium-graphite and we succeeded in preparing... 

Fortunately for silicon nomenclature, these rules were formulated and put into use before a lot of troublesome names were introduced. Thus, silicane for SiH4 was changed to silane, which has a host of derivatives. Disilicoethane became disilane, triethylsilicol became triethylsilanol, etc. The system of rules for the nomaiclature of organosilicon compounds is an excellent example of what can be accomplished if nomenclature problems in new or rapidly developing fields are studied and solved before bad practices become established. 

Reactions of 1,3-dienes with various disilanes were reported by means of group 10 transition-metal catalyst, giving synthetically useful allylic silane derivatives. Two major pathways, i.e., formation of 1 1 and 1 2 adducts, are known and controlled by the choice of disilanes and catalyst. 

Photochemistry of silane and its derivatives has been investigated extensively and a great deal of knowledge has been accumulated. Perkins and Lampe studied the direct photolysis of disilane at 147 nm and proposed the following primary processes (11 ),... 

The possibility of synthesizing alkyl and alkenyl silanes from olefins and acetylenes with silane, SiH, has been investigated by White and Rochow (128). With ethylene various ethyl derivatives of silane and disilane were obtained under conditions suggestive of a free-radical mechanism ... 

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