Boron trifluoride-Dimethyl sulfide

Related Reagents. Bis[4-(tridecafluorohexyl)phenyl] Diselenide l-(Butylseleno)-3,5-bis(heptadecafluorooctyl)-ben-zene l-(Butylseleno)-2,4-bis(heptadecafluorooctyl)benzene. 

Kasinath Sana Wayne State University, Detroit, MI, USA 

Physical Data solid at —78°C, liquid at rt Psatn(25°C) 217 mmHg.2  

Solubility sol most organic solvents such as pentane. 

Form Supplied in liquid complex sealed under nitrogen commercially available. 

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An alternative method of synthesizing the pyrazine compounds was described by Ghosh et al, and the synthesis is shown is Scheme 32 [78]. Reaction of a 1,2-dione (124) with a 1,2-diamine (125) to form an imine intermediate followed by spontaneous oxidation of the dihydropyrazine intermediate, formed the protected pyrazine compound 126. The free phenol 127 was obtained by removal of the methyl-protecting groups with a boron trifluoride-dimethyl sulfide complex. Similar compounds were prepared via the same method by Simoni et al. [79]. 

DEBENZY LATION Boron trifluoride-Dimethyl sulfide. 

Related Reagents. Boron Trifluoride-Acetic Acid Boron Trifluoride-Acetic Anhydride Boron Trifluoride Etherate Boron Trifluoride Dimethyl Sulfide Tetrafluoroboric Acid. 

Write an equation for the Lewis acid-Lewis base reaction between boron trifluoride and dimethyl sulfide [(0)3)25]. Use curved arrows to track the flow of electrons and show formal charges if present. 

Stannane 6a underwent facile transmetalation in tetrahydrofuran at — 78 °C on treatment with butyllithium to afford 6b. Addition of the lithium reagent 6b to a solution of 1.1 equivalents of copper(I) bromide-dimethyl sulfide in 1 1 diisopropyl sulfide/tetrahydrofuran at — 78 °C gave the copper reagent 6c, which reacted with methyl vinyl ketone at —78 "C in the presence of boron trifluoride-diethyl ether65, producing 7 in 55% yield65. 

In addition to standard catalytic hydrogenolysis, methods for transfer hydrogenolysis using hydrogen donors such as ammonium formate or formic acid with Pd-C catalyst are available.216 The Cbz group also can be removed by a combination of a Lewis acid and a nucleophile for example, boron trifluoride in conjunction with dimethyl sulfide or ethyl sulfide.217... 

A boron analog - sodium borohydride - was prepared by reaction of sodium hydride with trimethyl borate [84 or with sodium fluoroborate and hydrogen [55], and gives, on treatment with boron trifluoride or aluminum chloride, borane (diborane) [86. Borane is a strong Lewis acid and forms complexes with many Lewis bases. Some of them, such as complexes with dimethyl sulfide, trimethyl amine and others, are sufficiently stable to have been made commercially available. Some others should be handled with precautions. A spontaneous explosion of a molar solution of borane in tetrahydrofuran stored at less than 15° out of direct sunlight has been reported [87]. 

Fluoromalonates can be obtained in moderate yields by fluorination of the corresponding carbanions with xenon difluoride, dimethyl sulfide and boron trifluoride-diethyl ether complex.29... 

Dibromoborane-Dimethyl sulfide, 92 Dichloro(dimethylamino)borane, 120 Diisobutylaluminum hydride-Boron trifluoride etherate, 116 Diisopinocampheylborane, 117, 182 Diisopinocampheylmethoxyborane, 86 Dimesitylmethylborane, 8 Dimethoxy[l-trimethylsilyl-l,2-buta-dienyl]borane, 218 (R,R)- and (S,S)-frans-2,5-Dimethyl-borolanes, 119... 

Any of these BH3 compounds adds readily to most alkenes at room temperature or lower temperatures. The reactions usually are carried out in ether solvents, although hydrocarbon solvents can be used with the borane-dimethyl sulfide complex. When diborane is the reagent, it can be generated either in situ or externally through the reaction of boron trifluoride with sodium borohydride ... 

Reduction of esters, nitriles, and amides. These groups are rapidly reduced by horanc-dimcthyl sulfide in refluxing THF (b.p. 67°) if the dimethyl sulfide (b.p. 38°) is removed as liberated. Under these conditions, the reagent is comparable to uncomplexed diborane. Reduction of secondary and tertiary amides is best effected in the presence of boron trifluoride etherate otherwise, excess reagent is utilized for formation of complexes with the products. 

From Table III it is apparent that a number of different donors could be used to obtain very attractive fractionation factors. Indeed, at 30°C., the isotopic equilibrium constant was 1.03, or more, for phenetole, anisole, diethyl ether, ethyl formate, dimethyl selenide, dimethyl sulfide, and diethyl sulfide. However, all of these donors were not equally satisfactory for our purpose. The boron trifluoride complexes of the thioethers, the selenide, and the ester had a pronounced tendency toward irreversible decomposition and were too unstable to be seriously considered for an... 

Borane, which is used as a complex with tetrahydrofuran [992] or dimethyl sulfide [611, 992] or generated in situ from lithium borohydride with boron trifluoride etherate [646] or sodium borohydride with aluminum chloride [184], reacts with 3 mol of an alkene to form a tertiary borane. The oxidation with alkaline hydrogen peroxide [183, 992, 1201] or with trimethylamine oxide [991, 992] yields an alcohol (equations 598 and 599). 

Of the various types of higher order compounds which should be named as coordination compounds, only molecular addition compounds have not been considered. The rules for naming inorganic compounds indicate that (CHaJsN-BF would be called compound of boron trifluoride with trimethylamine., However, Davidson and Brown (4) suggest that this substance be called trimethylamine-boron trifluoride. In general, that molecule which donates a pair of electrons (base) is given first followed by the acceptor molecule (acid). Similarly, (CH3)2S-A1(CH3)3 would be known as dimethyl sulfide-trimethylaluminum. If these were named as coordination compounds, the names would be (trimethylamine)trifluoroboron and (dimethylsulfide)trimethylalu-minum. 

Reducing agents Aluminum hydride. Bis-3-methyl-2-butylborane. n-Butyllithium-Pyridine. Calcium borohydride. Chloroiridic acid. Chromous acetate. Chromous chloride. Chromous sulfate. Copper chromite. Diborane. Diborane-Boron trifluoride. Diborane-Sodium borohydride. Diethyl phosphonate. Diimide. Diisobutylaluminum hydride. Dimethyl sulfide. Hexamethylphosphorous triamide. Iridium tetrachloride. Lead. Lithium alkyla-mines. Lithium aluminum hydride. Lithium aluminum hydride-Aluminum chloride. Lithium-Ammonia. Lithium diisobutylmethylaluminum hydride. Lithium-Diphenyl. Lithium ethylenediamine. Lithium-Hexamethylphosphoric triamide. Lithium hydride. Lithium triethoxyaluminum hydride. Lithium tri-/-butoxyaluminum hydride. Nickel-aluminum alloy. Pyridine-n-Butyllithium. Sodium amalgam. Sodium-Ammonia. Sodium borohydride. Sodium borohydride-BFs, see DDQ. Sodium dihydrobis-(2-methoxyethoxy) aluminate. Sodium hydrosulflte. Sodium telluride. Stannous chloride. Tin-HBr. Tri-n-butyltin hydride. Trimethyl phosphite, see Dinitrogen tetroxide. 

C2HBF3S Dimethyl sulfide-boron trifluoride(l l)-complex 353-43-5... 

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