Über die ozonisierungsreaktion von jod in wasserfreiem fluorwasserstoff und die hydrolyse von jodtrifluorid

From the reaction of elemental iodine with ozone in anhydrous HF crystalline iodine trifluoride is formed. The hydrolysis of iodine trifluoride in HF yields a colourless crystalline solid. The Raman spectra of both compounds are described.     

BF3‐OEt2‐Mediated Rearrangement of (4‐Phenylpiperidin‐4‐Yl)‐Arylmethanols

Synthesis of several 4‐benzhydrylidenepiperidine analogs has been established starting from different (4‐phenylpiperidin‐4‐yl)‐arylmethanols via boron trifluoride etherate mediated rearrangement. The possible rearranged mechanism was proposed. Boron trifluoride etherate‐mediated rearrangement of the related derivatives was also examined. It presents a novel rearrangement reaction catalyzed by boron trifluoride etherate and broadens the scope of application.     

Boron trifluoride-mediated alkylation of diphenylphosphine with tert-alkyl fluoride

[reaction: see text] Treatment of tertiary alkyl fluoride with diphenylphosphine in the presence of a stoichiometric amount of boron trifluoride etherate yields the corresponding tert-alkyldiphenylphosphine despite the coexistence of the strong Lewis acid and the highly coordinating phosphine. Use of diphenyl(trimethylsilyl)phosphine as a nucleophile makes the reaction catalytic in boron trifluoride.     

Preparation of fluorine-containing polyethers

Polyethers were prepared from 3,3,3-trifluoro-1,2-epoxypropane by using both cationic and anionic initiators. Aluminum chloride and boron trifluoride were the two cationic initiators investigated. The polymer obtained with the use of aluminum chloride contained no functional endgroups other than hydroxyl, while the polymer prepared with boron trifluoride contained some terminal unsaturation. Potassium hydroxide and the monosodium salt of hexafluoropentanediol were investigated as anionic initiators. The polymer obtained by using potassium hydroxide also contained terminal unsaturation, while the polymer prepared with the monosodium salt of hexafluoropentanediol was terminated with primary hydroxyl groups capable of being used in polyurethanes. All polymers had molecular weights in the range from 970 to 4300. A fluorine-containing polyformal was prepared in high yield by the reaction of hexafluoropentanediol with trioxane. The same polymer was obtained in poor yield by the reaction of hexafluoropentanediol with dibutyl formal. Ring-opening polymerizations were attempted on two fluorinated cyclic ethers, 2,2,3,3,4,4-hexafluoropentamethylene oxide and 3,3,4,4-tetrafluorotetramethylene oxide. There was no reaction with anionic initiators. With most of the cationic initiators, there was no reaction. Boron trifluoride and phosphorus pentafluoride formed complexes with the ether, but would not cause ring opening.     

A ring opening reaction of oxetanes with lithium acetylides promoted by boron trifluoride etherate

Several substituted oxetanes were treated with lithium acetylides in the presence of boron trifluoride etherate to give f-hydroxyacetylenes. The reaction conditions were varied and several synthetic features of the present reaction were revealed.     

Donor-acceptor complexes of linear oligopyrroles with boron trifluoride. Spectral studies and quantum-chemical simulation

Intermediate products of synthesis of the boron trifluoride complexes with linear oligopyrroles are found. By means of electronic spectroscopy it was shown that the reaction of linear oligopyrroles with boron trifluoride in solutions resulted in the formation of stable donor-acceptor complexes. Their composition was established and the formation constants were evaluated. It was shown that transformation of these complexes in the corresponding borofluoride complexes is possible only while boiling the reaction mixture. By means of quantum-chemical methods the structural and energy parameters of the donor-acceptor complexes under study were calculated.     

Study of the reaction between boron trifluoride methanol complex and sodium methoxide

The reaction between boron trifluoride methanol complex and sodium methoxide in methanol solution was investigated using conductivity as the reaction indicator. The reaction conditions were examined and a mechanism of this reaction was proposed. Moreover, proper reaction conditions were proposed for boric acid preparation using this reaction.     

Boron fluorides of cis- and trans-2-aryl-3-aroylaziridines

The reaction of boron trifluoride etherate with cis- and trans-2-aryl-3-aroylaziridines yields the respective complexes in high yield. According to PMR spectral data the methyl group of boron trifluoride trans-1-methyl-3-aroylaziridines is located in syn-position, and in the cis-aziridine complexes in anti-position, to the carbonyl group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1047–1049, August, 1987.     

Stereoselective one-pot, three-component synthesis of 4-amidotetrahydropyran

The reaction of aldehyde with allylsilane in acetonitrile mediated by boron trifluoride etherate generated 4-aminotetrahydropyrans in good yields. The product is highly stereoselective.     

Studies on polyhaloalkanes Ⅱ.A facile method for mono-fluorination of α,ω-dihaloperfluoroalkanes

A faeilo monofluorination of α,ω-dihaloporfluoroalkanes was achieved by the reactionof them with antimony trifluoride and chlorine in anhydrous antimony pentachloride when mono-fluorinated products wero removed immediately after their formation from the reaction mixture byfractionation.The reaction conditions were also investigated.     

An efficient synthesis of dihydro- and tetrahydropyrans via oxonium-ene cyclization reaction

An efficient method has been developed for the synthesis of 2,3-dihydropyrans and 4-methylenetetrahydropyrans from aldehydes and substituted homoallyl alcohols in benzene mediated by boron trifluoride etherate in good yields. The reaction proceeds via oxonium-ene reaction.     

Oxonium ions as initiators for vinyl polymerizations. A reappraisal

Triethyl oxonium fluoroborate either preformed or preparedin situ by the reaction of boron trifluoride etherate with epichlorohydrin does not initiate the homo or copolymerization of vinyl monomers. Small conversions to copolymers by use of these initiators with low methyl methacrylate incorporation is ascribed to conventional vinyl copolymerizations, initiated by free boron trifluoride and/or protonic impurities in the system.     

Oxindoles from α-acyloxyamides

Oxindoies have been obtained in good yields from the reaction of several a-acyloxy-α,α-diphenylacetanilides and boron trifluoride etherate. The reaction probably occurs by hydrolysis of the ester followed by electrophilic substitution of the resultant carbonium ion on the anilide ring.     

Reaction of methyl hypochlorite with certain olefins in the presence of boron trifluoride

Fluoro chlorides are major products in the reaction of methyl hypochlorite with certain olefins in the presence of boron trifluoride.     

On the synthesis of chlorine pentafluoride

The reaction between chlorine trifluoride and elemental fluorine was studied in order to find the optimal reaction conditions for the synthesis of chlorine pantafluoride. It has been found that nickel difluoride is a very effective catalyst for the mentioned reaction. The obtained results are expressed as space-time-yield of chlorine pentafluoride.     

Reaction of tertiary cyclopropyl silyl ethers with diethylaminosulfur trifluoride. Part 2: The Friedel-Crafts allylation and cyclopropylation of electron-rich aromatic compounds

The reaction of tertiary cyclopropyl silyl ethers with diethylaminosulfur trifluoride in electron-rich aromatic compounds causes the Friedel-Crafts alkylation to produce allylated or cyclopropylated aromatic compounds.     

The chemistry of acetals

The reaction of butyndial tetramethylacetal with acetoacetic ester in the presence of boron trifluoride etherate is investigated, and is shown to give 5, 5′-dimethyl-4, 4′-dicarbethoxy-2, 2′-difuryl. The reaction is extended to synthesize some difuran derivatives.     

Investigations on boron compounds

Summary A method is proposed for the preparation of triallylborine by reaction between boron trifluoride and allyl-magnesium bromide; the desired product is obtained in 80% yield.     

Practical carbonyl-ene reactions of alpha-methylstyrenes with paraformaldehyde promoted by a combined system of boron trifluoride and molecular sieves 4A

[reaction: see text] A combined system of boron trifluoride and molecular sieves is an efficient promoter for the carbonyl-ene reaction of alpha-methylsyrenes with paraformaldehyde. The coexistence of BF3 x OEt2 and molecular sieves 4A is essential for obtaining high yields of ene products.     

Oxidative nucleophilic substitution: transformation of alkylboronic derivatives

An efficient amidation reaction is described in this paper. Potassium alkyltrifluoroborate salts can be transforming to amides from nitriles in the presence of copper acetate and boron trifluoride. An extension of this reaction allowed the formation of amines, ethers, and C-C bond.