Boron tetrafluoride

OrganometaUics and organometaHoids that yield peroxides in this manner include those in which Q is aluminum, antimony, arsenic, boron, cadmium, germanium, lead, phosphoms, siUcon, and tin and in which X is chlorine, bromine, alkoxy, acetoxy, cyano, oxide, hydride, hydroxyl, amino, alkyl, and boron tetrafluoride (28,33,44,60) (see Table 3). 

Step 1 1-(p-Chlorophenyl)-3-Ethoxy-1 H-lsoindole - Crystalline triethyloxonium boron-tetrafluoride (21 g) (prepared from 23 g of borontrifluoride etherate and 11 g of epichlorohydrin) is dissolved in 100 ml of absolute methylenechloride. 3-(p-Chlorophenyl) phthalimidine (21 g) is added and the reaction mixture is stirred overnight at room temperature. The resulting solution is poured onto 50 ml of saturated Sodium carbonate, extracted with 500 ml of ether and dried. Upon evaporation of the solvent there is obtained crude material which is recrystallized from methylene chloride/hexane (1 1) to yield l-(p-chlorophenyl)-3-ethoxy-1 H-isoindole MP 102° to 103°C. 

This outstanding behavior of bis(pentamethylcyclopendienyl)stannylene has been explained by the energetically favorable formation of the ionic compound 79 which contains the 6-membered cluster C5Sn 174>. The structure of the boron tetrafluoride compound is illustrated in Fig. 15 the tin atom in the cation is located at the apex of a pentagonal pyramide 173). 

Unlike nickel catalysts, palladium catalysts undergo neither cyclodimerization nor cyclotrimerization to form COD or CDT. Only one paper by Chepaikin and Khidekel reported that a mixture of divinylcyclobu-tanes was obtained from butadiene using palladium salts with noncom-plexing anions such as perchlorate and boron tetrafluoride (15). This is a big difference between the catalyses of palladium and nickel. 

Problem 2.9 Predict the shape of (a) the boron trifiuoride molecule (BE,) and (h) the boron tetrafluoride anion (BF ). All bonds are equivalent. <... 

Thus far no reports have appeared on the isolation of 1,3-ditellurolylium cation salts in a pure state. Attempts to prepare 1,3-ditellurolylium boron tetrafluoride and its derivatives via treatment of 1,3-ditelluroles with tri-phenylmethyl boron tetrafluoride in MeCN solution failed (82TL1531). However, formation of the 1,3-ditellurolylium cation 74 was revealed by the H NMR spectrum in which the 2-H proton was shown to give a very low-field triplet (8 15.0 ppm, 4/Hh = 1.2 Hz). Cation 74 is sufficiently stable in solution only at low temperature. When an acetonitrile solution of 74 obtained from 1,3-ditellurole was heated to 30°C, the initial H NMR spectrum drastically changed to the A2X spectral pattern (8 13.8 ppm, d and 10.3 ppm, /, iJ = 6.9 Hz) corresponding to the spectrum expected for the 1,2-ditellurolylium cation 75. A plausible reaction scheme is shown below. A further elevation of the temperature of the solution resulted in an unidentified destruction process accompanied by the extrusion of elemental tellurium. 

Benzo-1,3-ditellurolylium tetrafluoroborate 76 turned out to be the first preparatively isolated salt of a heterocyclic carbocation containing two tellurium atoms in a ring (91UP3). The synthesis of 76 was carried out, similar to its sulfur analog benzo- 1,3-dithiolylium boron tetrafluoride (76BCJ3567), by treatment of a solution of 2-butoxybenzo-l,3-ditellurole in acetic anhydride with 2 equivalents of HBF4. 

Apreton R Borate(l-), tetrafluoro-, sodium Boron sodium fluoride (BNaF4) EINECS 237-340-6 NSC 77386 Pyricit Sodium borofluoride Sodium boron fluoride Sodium boron tetrafluoride Sodium fiuoborate Sodium fluoborate (Na(BF4 Sodium fluoroborate (NaBF4) Sodium tetrafluoroborate Sodium tetrafluoroborate 1-). Used as a fluorinating agent. Rectangular prisms mp = 384° = 2.4700 soluble in H2O (108 g/100 ml), less... 

Boron tetrafluorides decompose i nto gaseous boron trifluoride (BF3) which acts in the flame front. For example ammonium boron tetrafluoride (NH4BF4), recommended for polyolefins, dissociates into ammonia (NH3), hydrogen fluoride (HF), and boron trifluoride. 

In addition to free radical polymerizations, however, cationic and anionic polymerizations may, depending on solvent used, also be observed. The anodic discharge of acetate ions into the homogeneous phase, for example, produces a free radical polymerization of styrene or acrylonitrile. The anodic discharge of perchlorate or boron tetrafluoride ions, on the other hand, leads to the cationic polymerization of styrene, iV-vinyl carbazole, and isobutyl vinyl ether. In contrast, the cathodic decomposition of tertaalkyl ammonium salts induce acrylonitrile to polymerize anionically. 

In addition to iodonium, sulfonium and selenonium compounds, onium salts of bromine, chlorine, arsenic, and phosphoras are also stable and can act as sources of cation radicals as well as Bronsted acids, when irradiated with light. Performance of diaryl chloronium and diaryl bromonium salts was studied by Nickers and Abu. Also, aryl ammonium and aryl phosphonium, and an alkyl aryl sulfonium salt were investigated. It appears that the general behavior of these materials is similar to diphenyl iodonium and triphenyl sulfonium salts. These are formations of singlet and triplet states followed by cleavages of the carbon-onium atom bonds and in-cage and out of cage-escape reactivity. The anions of choice appear to be boron tetrafluoride, phosphorus hexafluoride, arsenic hexafluoride, and antimony hexafluoride. 

Li and collaborators devised a facile, clean, one-pot approach to the synthesis of 2,7-diamino-5-aryl-3,4,5-8-tetrahydro-4-oxopyrido[2,3-with aromatic aldehydes and malononitrile in an ionic liquid, specifically, 1-butyl-3-methylimidazolium (bmim) boron tetrafluoride (Scheme 46) (13JHC534). 

---