Diphenyl tetrafluoroborate

Triphenylsulfonium tetrafluoroborate [(C6Hs)3 S" BF4 ] is used instead of diphenyl iodonium chloride to give phenyl radical as the initiating species. Potassium [tris(oxalato) cobaltate) (III)] with diphenyl iodonium chloride also has been used as the photoinitiator of acryl-... 

Olah and coworkers56 found that treatment of dialkyl, arylalkyl and diaryl sulphides with nitronium hexafluorophosphate (or tetrafluoroborate) 32 at —78° in methylene chloride resulted in the formation of sulphoxides in moderate to high yields (Table 3). In the oxidation of diphenyl sulphide which affords diphenyl sulphoxide in 95% yield, small amounts of the ring nitration products (o- and p-nitrophenyl phenyl sulphides) were formed. However, diphenyl sulphone and nitrophenyl phenyl sulphoxide were not detected among the reaction products. 

Azidomethylbenzenediazonium tetrafluoroborate, 2708 Benzenediazonium tetrafluoroborate, 2223 2-Chloro-3-pyridinediazonium tetrafluoroborate, 1816 5-(4-Diazoniobenzenesulfonamido)thiazole tetrafluoroborate, 3119 5,6-Diphenyl-l,2,4-triazine-3-diazonium tetrafluoroborate 2-oxide, 3677... 

The meso-ionic l,2,4-triazol-3-ones (200) are stable to acid, but alkaline hydrolysis gives 1,4-disubstituted semicarbazides. They do not normally participate in 1,3-dipolar cycloadditions, but the meso-ionic 1,4-diphenyl-l,2,4-triazol-3-one (200, R = R = Ph, R = H) and benzyne yielded 2-phenylindazole. 1,2,4-Triazolium salts (211) are formed with triethyloxonium tetrafluoroborate. Reduction of the meso-ionic compound 200, R = Me, R = R = Ph, with lithium aluminum hydride gives the triazolidinone 212. ... 

The salts (298) " undergo a nucleophilic displacement with arylamines, yielding intermediate tetrafluoroborates, which with ethanolic sodium hydroxide yield red meso-ionic l,2,3,4-thiatriazol-5-imines (299). The dipole moment of the diphenyl derivative in benzene is 3.7 D. ... 

Another and still more stabilized carbenium-phosphonium-oxonium-tetra-fluoroborate 225 can be prepared when bis-4.4- (l, l-dimethoxy-2.6-diphenyl-X -phosphorin)-methane 224 is treated with triphenylcarbenium-tetrafluoroborate. 

A most interesting reaction was found when the tetrafluoroborate 221 in acetonitrile was treated with water or with weak aqueous bases. Instead of the expected hydroxymethyl derivative 230, only the 4.4 -bis-(l. l-dimethoxy-2.6-diphenyl-... 

Under the same conditions 233b forms an analogous compound, whereas 1.1-di-methoxy-2.6-diphenyl-4-dimethylcarbenium-X -phosphorin-tetrafluoroborate 233, R and H = CH3) with bases produces the monomeric olefin (1.1-dimethoxy-2.6-diphenyl-4-isopropenyl-X -phosphorin). 

When l,l-dimethoxy-4-propyl-2,6-diphenyl-A5-phosphorin (53) is transformed into its 4-carbenium tetrafluoroborate (54) and treated with a base the 4-(l-propenyl) derivative (55) is formed. This, by a two phase oxidation with KMn04, gives the aldehyde (56) which can be further transformed, e.g. into the nitrile (57 equation 34) (75AG(E)lll). An Arbusov type dealkylation of the cation salts (49) (or 54) with LiBr gives the phosphinic ester (58 equation (35)). 

Treatment of 2-(rm-butylthio)-116-benzyl-3,4-diphenyl-2,6,7,116-tetrahydro[l,3]thiazino[2,3-a]isoquinoline with trityl tetrafluoroborate in acetic anhydride at 0°C gave 116-benzyl-3,4-diphenyl-6,7-dihydro-... 

It has been reported that diphenyliodonium triflate reacts with the lithium enolates of some cyclic ketones in the presence of copper cyanide to yield the corresponding a-phenylated or a-diphenylated ketones.58 There has been a detailed analysis of the products of thermal decomposition of diphenyliodonium tetrafluoroborate and hexafluorophosphate salts.59... 

In contrast to trialkyloxonium salts, the triphenyloxonium salt 34 can be obtained by the reaction of benzenediazonium tetrafluoroborate with diphenyl ether in poor (2%) yield [Eq. (4.20)] and is extremely inert toward nucleophiles. This fact is clearly demonstrated by the remarkable stability of triphenyloxonium halides (Cl, Br, ... 

Alkynylphenyliodonium tetrafluoroborates selectively transfer the unsaturated group to diphenyl chalcogens to form 1-alkynyldiphenyIonium ions290... 

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