Silicon fluorination

McFeely F R, Morar J F and Himpsel F J 1986 Soft x-ray photoemission study of the silicon-fluorine etching reaction Surf. Sc/. 165 277-87... 

When fluorine is beta to siUcon, compounds undergo a facile elimination of an ethylenic compound and again form the stable silicon—fluorine bond... 

Chlorine Non-metals Cobalt trifluoride Silicon Fluorine Non-metals Iodine pentafluoride Metals, etc. 

Nielsen FH, Sandstead HH. 1974. Are nickel, vanadium, silicon, fluorine, and tin essential for man. Ann J Clin Nutr 27 515-520. 

Interestingly it is also possible to form a stable silicon-fluorine bond by treatment of a methoxysilole with boron-tnfluonde etherate or of a silole with trityl tetrafluoroborate [106] The resultant fluorosilane is also a building block for further transformations of the silole (equation 84)... 

It was found that silicon-bromine and silicon-chlorine bonds were thermodynamically activated towards substitution by coordination of an oxygen nucleophile, whereas coordination was found to deactivate the silicon-fluorine bond. 

Aluminum is the most abundant metallic element in the earth s crust, comprising approximately 8% of the crust (Brusewitz 1984). Aluminum does not occur naturally in the metallic, elemental state, but rather occurs in combination with oxygen, silicon, fluorine, and other elements (Browning 1969 Dinman 1983 IARC 1984 NRC 1982). The most important raw material for the production of aluminum is bauxite, which contains 40-60% alumina (aluminum oxide) (Dinman 1983 IARC 1984). Other raw materials sometimes used in the production of aluminum include cryolite, aluminum fluoride, fluorspar, corundum, and kaolin minerals (Browning 1969 Dinman 1983 IARC 1984). 

Bossier, J. M., P. L. Timms, and J. L. Margrave Silicon-Fluorine Chemistry. III. Infrared Studies of SiF2 and its Reactions in Low-Temperature Matrices. Inorg. Chem. 5, 729 (1966). 

D. D. Stump, R. A. Kent, and J. L. Margrave Silicon-Fluorine Chemistry. IV. The Reaction of Silicon Difluoride with Aromatic Compounds. J. Amer. chem. Soc. 88, 940 (1966). SiF2. Expanding Silicone-Fluorine Chemistry. Chem. Engng. News 43, 40 (1965). 

An ether protecting group can be difficult to remove (deprotect). It often requires strong acid, which can react with the free hydroxyl group or other parts of the molecule. Ethers based on silicon (silyl ethers) are much easier to remove than carbon-based ethers. In aqueous or organic solvents, fluoride ion removes silyl ethers under gentle conditions because the silicon-fluorine bond is exceptionally strong. 

Fluorosilane. A fluorine derivative of a silane a compound of silicon (other than fluosilicic acid or a fluosilicate) containing at least one silicon-fluorine linkage. 

The first observation of penta- and hexaeoordinate silicon compounds was reported at the beginning of the 19th century by Gay-Lussac [87] and Davy [88], Subsequent investigation of hypercoordination in silicon compounds stimulated widespread use of nucleophilic activation and catalysis in the application of organosilicon compounds as reactive species in organic synthesis. Synthetic application for silicon-fluorine bond formation can be found in several reviews over the last two decades, and this section focuses on recent advances in the use of hypervalent organosilicon compounds in selective organic synthesis, in particular, selective carbon-carbon bond formation [89]. 

The covalent character of the silicon fluorine bond in 5 is evidenced by the observation of an Si-F coupling constant (see Table 1). 

Addition of F or a protic solvent (water, alcohol) causes an upfield shift of the resonance accompanied by line broadening with concommitant loss the silicon-fluorine hyperfine structure. 

Analysis of a newly discovered gaseous silicon-fluorine compound shows that it contains 33.01 mass % silicon. At 27°C,... 

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