Tetrakis -, lithium

Chlorotris(diethylamino)titanium24 is prepared directly from diethylamine, lithium and tilani-um(IV) chloride in the presence of styrene as reducing agent25. However, a metathesis reaction between tetrakis(diethylamino)titanium26 28 and titanium(lV) chloride gives a cleaner product and is thus preferred. Bromotris(diethylamino)titanium is prepared similarly7,29. 

Natrium-trimethoxy-hydrido-borat Lithium-tri-tert. -bu tyloxy-hydrido-aluminat Lithium-(tetrakis-[N-dihydropyridyl]-aluminat)... 

Natriumboranat/Pyridin > Lithium-tetrakis-[l,2-dihydro-pyridyl-(l)]-aluminat > Natriumboranat/Alkohol > Lithium-tri.-tert.-butyloxy-hydrido-aluminat > Lithiumalanat > Lithium-trimethoxy-hydrido-aluminat > Aluminiumhydrid > Bis-[2-methyl-propyl]-aluminiumhydrid... 

This complex is not the actual catalyst for the hydrovinylation, but needs to be activated in the presence of a suitable co-catalyst. The role of this additive is to abstract the chloride ion from the nickel centre to generate a cationic allyl complex that further converts to the catalytically active nickel hydride species. In conventional solvents this is typically achieved using strong Lewis acids such as Et2AlCl. Alternatively, sodium or lithium salts of non-coordinating anions such as tetrakis-[3,5-bis(trifluoromethyl)phenyl]borate (BARF) can be used to activate hydrovinylation... 

A convenient route to andiides, where Li and A1 centers are, at the same time, involved is represented by the reaction of LiAlH4 with primary silylphosphanes and silylarsanes (Scheme 4) (67). However, the outcome of such reactions is dependent on the stoichiometry. The silylarsane 2c reacts with LiAlH4 in the molar ratio of 4 1 in 1,2-dimethoxyethane, under evolution of H2, resulting in the corresponding tetrakis(arsaneyl)-substituted lithium alanate 36c in quantitative yield. The similar transformation of the arsane 2a with LiAlH4 in the... 

Thorpe reaction org chem The reaction by which, in presence of lithium amides, a,(rt-dinitriles undergo base-catalyzed condensation to cyclic iminonitriles, which can be hydrolyzed and decarboxylated to cyclic ketones. thorp re,ak-shan TMPC See tetrakis(hydroxymethyl)phosphonium chloride, thulia See thulium oxide. thu-le-a ... 

Several examples of carbenoid ion-radicals are discussed within this book. A silylene anion-radical preparation and properties is exemplified here. Scheme 2.5 shows the path to this species. Tetrakis(di-tert-butytmethylsilyl)disilylene was reduced by lithium or sodium salt of naphthalene anion-radical in THF at 78°C and then 12-crown-4 was added to the resulting reaction mixture. The silylene anion-radical was obtained as the corresponding alkali salt. Red crystals of the salt were isolated and characterized by ESR spectroscopy and x-ray crystallography (Inoue et al. 2007). 

Lithium aluminum hydride dissolves in pyridine and forms lithium tetrakis-(A -dihydropyridyl)aluminate which itself is a reducing agent for purely aromatic ketones [440, 441]. 

Heteroaromatics are subdivided, according to the electron influence of the heteroatom, into w-electron-deficient compounds and compounds with an excess of it electrons on the ring carbon atoms. The typical ff-electron-delicient compound pyridine has so far been made to react only in one case the reaction of lithium tetrakis(A-dihydropyridyl)-aluminate (LDPA) [112-114), obtainable from pyridine and lithium aluminum hydride, with trifluoromethanesulfenyl chloride in an excess of pyridine affords 3-trifluoromethylmercaptopyridine in low yield (13%) (60). This reaction probably occurs through sulfenylation of the l,2-dihydrop5T idyl moiety of the LDPA with the formation of a 2,5-... 

In the group of Sekiguchi, the dilithiated derivatives of tetrakis- and hexakis(trimethyl-silyl)benzene 226 and 228 in Schemes 78 and 79, respectively, have been synthesized by the reaction of the parent compounds with an excess of metallic lithium in coordinating solvents at room temperature. Both molecular structures in the solid state were cleared up by X-ray structural analysis (Figures 29 and 30) . 

The reduction of l,l-bis(diphenylphosphanyl) ethylene (248) with an excess of metallic lithium, activated by ultrasonic irradiation, leads to C—C coupling under the formation of a l,l,4,4-tetrakis(diphenylphosphanyl)butane (249) (Scheme 88)". Surprisingly, the lithium centres in the resulting dilithium compound do not form any lithium-carbon contacts, being coordinated by two diphenylphosphanyl groups and two TFIF molecules each. With this strucmral motif, the molecular structure is similar to the one of tris(phosphaneoxide) 20 (Section n. A), also obtained by Izod and coworkers upon deprotonation. ... 

The iodo benzamide derivative of pyrrolo[2,l-c][l,4]benzodiazepine 367 (R = I, Scheme 75, Section 5.1.1) reacts with bis(tributyl)tin, lithium chloride and tetrakis(triphenylphosphine) palladium(O) in refluxing dioxane to yield the stannyl derivative 370. The latter couples with substituted aryl bromides in the presence of... 

The lithium tetrakis (dihydrogenphosphido) aluminate, which is soluble in diglyme, shows typical organic and inorganic substitution reactions and can be used to introduce PH2 groups into molecules. The compound is quantitatively hydrolysed thus ... 

A, Dimethyl (s)-2-hexenedioate. A 100-roL, one-necked, round-bottomed flask is capped by a septum, swept with dry nitrogen and flame-dried. The flask is charged with methyl acrylate (50 ml, 0.55 mol. Note 1), then anhydrous lithium tetrafluoroborate (9 g, 0.096 mol, Note 2), and finally tetrakis(acetonitrile)palladium tetrafluoroborate (1.33 g, 0.003 mmol. Note 3). The mixture is stirred briefly until homogeneous. It is warmed under nitrogen in a 40°C-o11 bath for 72 hr (Note 4) and then allowed to cool to room temperature. The mixture is added to saturated aqueous sodium bicarbonate (100 mt) and extracted with ether (3 x 50 mt). The combined ether extracts are dried over anhydrous magnesium sulfate, filtered and concentrated to an oil with a rotary evaporator. The residue is distilled through a lO-cm... 

Sekundare und tertiare, aliphatische Nitro-Verbindungen, deren Nitro-Gruppen durch Allyl-, Benzyl- oder Oxiranyl-Funktionen desaktiviert sind, lassen sich durch radikalisch initiierte, nukleophile Substitution mit Natrium-arensulfinat in Phosphorsaure-tris-[dime-thylamid] bzw. Dimethylformamid unter Zugabe von Tetrakis-[triphenylphosphan]-pal-ladium(0)1-3 (Methode ) oder Lithium-2-nitro-propan4 (Methode ) in die entspre-chenden Aryl-sulfone uberfuhren (s.Tab. 43, S. 377) ... 

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