Phenyldiazonium tetrafluoroborate

Benzo-l,2,3,4-tetrazine 1-lV-oxides 13 can be obtained by intramolecular cyclisation of 2-(r-butylazoxy)phenyldiazonium tetrafluoroborates 11 which leads to 2-(r-butyl)benzo-1,2,3,4-tetrazinium 4-A/ oxides 12 via N to N migration of the r-butyl group followed by... 

Like its sulfur and selenium analogs, 2,6-diphenyl- 1,4-ditellurofulvene 2 on treatment with amyl nitrite and phenyldiazonium tetrafluoroborate undergoes electrophilic substitution at the terminal methine carbon, giving rise to the corresponding nitroso and phenylazo derivatives (81CC828). 

Thermolysis of 2-(azidomethyl)phenyldiazonium tetrafluoroborate and organic nitriles at 70 "C affords 2-substituted quinazolines in moderate to good yields. 

Electrochemically generated radicals, as for instance phenyl radicals formed by reduction of phenyldiazonium tetrafluoroborate, may be trapped by 81 c and detected by the ESR spectrum of the corresponding aminyloxide95. ... 

In the same program, phenyldiazonium tetrafluoroborate was allowed to react with two molecules of a nitrile (RCN) at 20°-50°C to obtain 2,4-disubstituted (phenyl or benzyl) quinazolines in good yields. The nitrilium salt 58 was thought to be the first stage 41,42 Somewhat similarly, phenyldiazonium tetrafluoroborate reacted with methyl isothiocyanate to give 2,4-di(methylthio)quinazoline.41... 

To a solution of 4-hydroxy-3-(methoxycarbonyl)phenyldiazonium-tetrafluoroborate (133 mg, 0.500 mmol) and Pd(OAc)2 (3.0 mg, 2.5 mol%) in dry and degassed methanol (5 mL) was added potassium 2,4-difluorophenyltrifluoroborate (110 mg, 0.500 mmol). The solution was stirred for 12 h at ambient temperature. Active charcoal (100 mg) was added, and the solution was evaporated in vacuo. The residue was extracted with MTBE in an ultrasonic bath, filtered through celite, and evaporated. The residue was purified by chromatography on silica (hexanes/MTBE 1 2) to give the title compound (130 mg, 0.490 mmol, 99%) as a colorless solid mp 97-99 °C. ... 

Compounds of the form RN2 X are named by adding the suffix -diazonium to the name of the parent compound RH, the whole being followed by the name of X- (Rule C-931.1, e.g., methanediazonium tetrafluoroborate, benzenediazonium chloride, not phenyldiazonium). Following RC- 82.2.2.3 (IUPAC, 1993), diazonium ions may also be named structurally on the basis of the parent cation diazenylium HNJ, e.g., benzenediazenylium ion. We name the substituent — NJ diazonio (not diazonium) following the same rule. Diazonio describes both mesomeric structures — N = N and — N = N. If one wants to describe one of these structures only, diazyn-l-ium-l-yl or diazen-2-ylium-l-yl has to be used for -N = N or -N = N, respectively. In the General Subject Index of Chemical Abstracts and in Beilstein, diazonium compounds as a class are indexed under this heading. 

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