Iodide lithium alloys

In an attempt to prepare (C3F7)4Si, silicon tetrachloride was treated with the lithium alloy and heptafluoro-n-propyl iodide. Hexafluoropropene and a mixture of fluorosilanes, (C3F7),SiF4, j, were formed. A similar reaction with tin tetrachloride led to formation of tin tetraiodide, very probably by... 

Lanthanide iodide silicides, 200 Lanthanide metals, 200 Lanthanide nitrobenzoates, 200 Lanthanide—transition metal alloy hydrides, 201 Lassaigne test, 201 Lead salts of nitro compounds, 201 Lecture demonstrations, 202 Light alloys, 202 Lime fusion, 202 Linseed oil, 202 Liquefied gases, 203 Liquefied natural gas, 203 Liquefied petroleum gases, 203 Liquid air, 204 Liquid nitrogen cooling, 205 Lithium peralkyluranates, 205 Lubricants, 205 Lycopodium powder, 205... 

Ethers Aiuminum bromide. Aluminum chloride. Boron tribromide. Boron trichloride. Diborane. Diphenyl phosphide, lithium salt. Hydrobromic acid. Hydriodic acid. Lithium bromide. Lithium bromide-BFt etherate. Lithium diphenyl. Methylmagnesium iodide. Pyridine hydrochloride. Sodium iodide. Sodium-Potassium alloy. Triphenylphosphine dibromide. 

T1C1 was treated with two molar equivalents of methyl lithium, giving a finely divided black precipitate. The later addition of methyl iodide caused the precipitate to disappear, leaving a clear solution of trimethylthallium. Previous attempts to cause methyl iodide to react with ordinary forms of thallium (lump metallic, Na-Tl alloy, and Tl-Cu couple) had all failed.80) The above reaction worked also with iodobenzene, although the yield was lower (79%) and reflux at 55 °C was needed. 

Various other reagents can be used for this reductive debromination. 1,2-Dipropylcyclopropane was prepared from 4,6-dibromononane using chromium(II) perchlorate in dimethylformami-de/water (yield 93%), lithium amalgam in tetrahydrofuran (75%), lithium biphenylide in te-trahydrofuran (78%), potassium-sodium alloy in tetrahydrofuran (68%), zinc dust and zinc(II) chloride in propan-2-ol/water (95%) and alkyllithiums in tetrahydrofuran (BuLi 16%, i-BuLi 18%, t-BuLi 47%). Ring closure of 1,3-dibromobutane to methylcyclopropane was achieved by treatment with zero-valent copper, which was obtained from reaction of lithium naphthalen-ide and copper(I) iodide/tributylphosphane in tetrahydrofuran (yield 91%) ... 

A few modifications of this reaction are the reaction between alkyl iodide and copper-zinc alloy, the reaction between zinc and a mixture of alkyl iodide and alkyl bromide, the transmetalation between zinc and lithium, magnesium, or tin, and the iodine-zinc exchange. ... 

Indeed separate experiments showed that lithium iodide reacts both with tin tetrachloride and with germanium tetrachloride, so that perfluoro-n-propyllithium made via the lithium-sodium alloy cannot be used to prepare (n-C3F7)4Sn and (n-C3F7)4Ge. Nevertheless, it is now established that perfluoro-re-propyllithium may be used to synthesize a number of new perfluoropropyl derivatives of Group IV elements, and probably similar compounds of other elements as well (9). As a result it is likely that perfluoro-alkyllithium compoimds will play a more important part in synthetic work in the future than they have in the past. 

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