Boron trifluoride etherate sulfide

Thiol esters can be reduced to sulfides or aldehydes. Alone generated from lithium aluminum hydride and boron trifluoride etherate [1099] or aluminum chloride [1100] in ether reduced the carbonyl group to methylene and gave yi-9y /o yields of sulfides. Phenyl thiolbenzoate failed to give the sulfide, and phenyl thiolacetate gave only an 8% yield of ethyl phenyl sulfide [1100]. 

Neopentyl sulfides have been prepared by alkylation of sodium sulfide with neopentyl tosylate in high-boiling polar solvents,4,5 or in low yields by reduction of alkyl 2,2-dimethylpropanethioate with the combination of lithium aluminum hydride and a large excess of boron trifluoride-etherate. ... 

Spiro compounds Boron trifluoride etherate, 43 Potassium ferricyanide, 255 Triphenyltin hydride, 335 Sulfides... 

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... 

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. 

AMINO GROUP Boron trifluoride ether-ale. l-r-Bulyloxycarbonyltriazole-1,2,4, Di-t-butyl dicarbonate. 4-Dimethylamino-1-t-butyloxycarbonyl pyridinium chloride. CARBONYL GROUP Ceric ammonium nitrate. 1,2-Dihydroxy-3-bromopropane. Sodium N-chloro-p-toluenesulfonamide. Thallium(lll) nitrate. Trichloroethanol. Trimcthylsilyl cyanide. Chloromethyl methyl sulfide. N,N -Diisopropylhydra-zinc. Trichloroethanol. 

Oxidations with m-chloroperoxybenzoic acid are carried out in solutions in hexane, dichloromethane, chloroform, methanol, or tetrahydro-furan at temperatures ranging from -78 to 40 C. The applications of m-chloroperoxybenzoic acid are epoxidation [287, 314, 315, 316] the Baeyer-Villiger reaction [286, 315, 317, 378] and the oxidation of primary amines to nitro compounds [379], of tertiary amines to amine oxides [320], of sulfides to sulfoxides [327, 322, 323, 324], and of selenides to selenones [325]. Secondary alcohols are oxidized to ketones in the presence of hydrogen chloride [326], and acetals are oxidized to esters with boron trifluoride etherate as a catalyst [327]. The addition of potassium fluoride to reaction mixtures facilitates product isolation, because both m-chloroben-zoic acid and the unreacted m-chloroperoxybenzoic acid are precipitated... 

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). 

The reaction of propargylic esters with aldehydes and hydrogen sulfide in the presence of boron trifluoride etherate leads to 1,3-dithiins (86) (Equation (56)) <71T5753>. Dieckmann cyclization of suitably substituted acyclic 1,3-dithioacetals gives rise to l,3-dithian-5-ones (87) (Equation (57)) <59LA(624)79, 63LA(661)84>. 

A mixture of the thiol (0.11 mole) and boron trifluoride-ether (2 drops) are stirred and heated on a steam-bath while the sulfide (0.05 mole) is dropped in during about 45 min. 

Borabicyclo[3.3.1] nonane, 47-49 9-Borabicyclo[3.3.1] nonane-pyridine, 4 Borane-Dimethyl sulfide, 49-50, 174 Borane-Pyridine complex, 50-51 Botch reduction, 452-453 Boron trifluoride etherate, 51-52, 354, 402,478,480,502... 

Organoboranes are obtained by addition of borane or alkyl boranes to alkenes (or alkynes). Borane itself can be prepared by reaction of boron trifluoride ether-ate with sodium borohydride. Borane exists as a dimer, but solutions containing an electron donor, such as an ether, amine or sulfide, allow adduct formation. The complexes BHa-THF and the borane-dimethyl sulfide complex BH3 SMc2 are commercially available and provide a convenient source of borane. The dimethyl sulfide complex is more stable than BHa-THF and has the additional advantage that it is soluble in a variety of organic solvents, such as diethyl ether and hexane. 

Preparative Methods made by the addition of equimolar amounts of the two components at —78°C. Dissociation of the complex reported as 96.2% at 12 °C and 97.4% at 340c 2a formed when crystalline bromodimethylsulfo-nium tetrafluoroborate is aspirated at rt to give a colorless product without change in crystal form. The reagent system is normally assembled by adding a large excess of dimethyl sulfide to an excess of boron trifluoride etherate. ... 

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