Tetrabutylammonium Iodid

Boujlel and Simonet used an electrochemical method to prepare a group of similar compounds, including compound ]5, shown in Eq. (3.41). In a typical case, benzil was reduced in DMF solution at the dropping mercury electrode in the presence of tetrabutylammonium iodide, used in this case as a supporting electrolyte rather than phase transfer catalyst. In the presence of diethylene glycol ditosylate, compound 15 (mp 77— 78°) was isolated in 10% yield. Using the same approach, acenaphthenedione was reduc-tively cyclized with triethylene glycol ditosylate to afford the product (mp 84—85°, 42% yield) shown in Eq. (3.42). 

Tetrabutylammonium iodide in trifluoroacetic anhydride is an effective reducing reagent [dS] This system can be used for direct reduction of arenesulfonic acids to the corresponding thiols or disulfides m moderate yields under mild conditions (equation 18) Alkanesulfonic acids are reduced by this system to disulfides with 30-57% yields [dfi]... 

TBAP, tetrabutylammonium perchlorate TEAB, tetraethylammonium bromide TBAI, tetrabutylammonium iodide. 

For the reaction of butyl bromide with tin, to give BuaSnBr and BugSnBrg (approximately equimolar), tetrabutylammonium iodide was found to be the best catalyst, and the mechanism was proposed (41) to be as follows. 

Oxazolines have also been obtained from aziridines and carboxylic imidazolides via iV-acylaziridinesJ1271 Isomerization of the Af-acylaziridines can be achieved by heating with a catalytic amount of tetrabutylammonium iodide or bromide. The transformation can be carried out as a one-pot reaction in quantitative yield (solvents THF, CHC13, benzene) with a wide spectrum of substituents R (R = H, alkyl, c-C6Hi i, C6H5,3-pyridyl). 

Current single-mode continuous-flow microwave reactors allow the processing of comparatively small volumes. Much larger volumes can be processed in continuous-flow reactors that are housed inside a multimode microwave system. In a 2001 publication, Shieh and coworkers described the methylation of phenols, indoles, and benzimidazoles with dimethyl carbonate under continuous-flow microwave conditions using a Milestone ETHOS-CFR reactor (see Fig. 3.11) [104]. In a typical procedure, a solution containing the substrate, dimethyl carbonate, 1,8-diazabicy-clo[5.4.0]undec-7-ene (DBU) base, tetrabutylammonium iodide (TBAI), and a solvent was circulated by a pump through the microwave reactor, which was preheated to 160 °C and 20 bar by microwave irradiation (Scheme 4.31). Under these condi-... 

Reaction of glycosyl thioimidate 79 with aa -dibromo-m-xylene in the presence of NaH as a base and 15-crown-5 as a supporting reagent allowed the intermediate 80 (Scheme 4.88). Treatment of the diol 81 with dibutyltin oxide in dry toluene and then reaction with 80 in the presence of tetrabutylammonium iodide afforded the desired O-linked intermediate 82. Activation of this compound with NIS-TMSOTf afforded 83 in a good yield. Hydrogenolysis followed by acetylation gave the desired disac-... 

Herriott and Picker (1975) have studied the reaction between sodium thiophenoxide and 1-bromobutane in benzene-water catalysed by various quaternary ammonium salts and by the dicyclohexyl-18-crown-6 isomers ([20] + [21]). The catalytic activities, as judged from the second-order rate constants, span a range of 104. The best catalyst appeared to be dicyclohexyl- 18-crown-6, directly followed by tetrabutylphosphonium chloride and tetrabutylammonium iodide. 

Materials Required Tetrabutylammonium iodide 40 g absolute methanol 90 ml silver oxide 25 g dry toluene 150 ml. 

Preparation of 0.1 M Tetrabutylammonium hydroxide (1 Litre) Dissolve 40 g of tetrabutylammonium iodide in 90 ml of anhydrous methanol, add 20 g of finely powdered silver oxide and shake vigorously for 1 hour. Centrifuge a few ml of the mixture and test the supernatant liquid for iodides. If a positive reaction is obtained add a further 2 g of silver oxide and shake for 30 minutes. Repeat this procedure until the mixture is free from iodides, filter through a fine sintered-glass filter and wash the reaction vessel and filter with three 50-ml quantities of toluene. Add the washings to the filtrate and add sufficient toluene to produce 1000 ml. Pass dry carbon-dioxide free N2 through the solution for 5 minutes. 

Example The El mass spectrum of tetrabutylammonium iodide shows a peak of low intensity (0.6 %) for the [BujN] ion, m/z 242. A molecular ion of the salt that eventually might occur at m/z 369 is not observed. The majority of the sample decomposes and the spectrum closely resembles that of pure tributylamine showing its molecular ion peak at m/z 185 (the fragmentation of which is explained in Chap. 6.11.1). A closer look, however, reveals the existence of peaks at m/z 127 and 128 corresponding to I and HI, respectively (Eig. 6.42). 

Fig. 6.42. El mass spectrum of tetrabutylammonium iodide. The intensity scale is 20fold above m/z 220, i.e., disregarding the peaks at m/z 127 and 128 this spectrum is very similar to the mass spectmm of pure tributylamine (Eig. 6.43b for the field desorption mass spectrum cf. Chap. 8.5.3).

To a three-neck 100 mL round-bottom flask was added 3-methoxyphenol (6.47 g, 52.09 mmol), tetrabutylammonium iodide (131.9 mg, 0.36 mmol) and dichloromethane (40 mL), resulting in a red-orange solution. 

The Liotta procedure involved slurrying coal in an aqueous solution of tetrabutylammonium hydroxide to remove acidic protons, followed by addition of methyl iodide as alkylating agent. This mixture was then stirred vigorously for 12-72 hrs. depending upon the extent of alkylation desired. After all lation, the moist coal sample was roto-evaporated to remove excess THF and methyl iodine, followed by exdiaustive extraction with water to remove tetrabutylammonium iodide produced during all lation. Finally, the treated coal was vacuum dried (50 C, 0.1 torr, 24 hours) before use. 

B. 2-(N-Benzyl-N-mesitylenesulfonyl)amino-1-phenyl-1-propanol, 3. A mixture of 2 (16.7 g, 50 mmol), benzyl chloride (6.90 mL, 60 mmol) (Note 1), tetrabutylammonium iodide (200 mg) (Note 1) and potassium carbonate (8.4 g, 60 mmol) in acetonitrile (100 i L) is heated under reflux for 17 hr (Note 4). The cooled mixture is filtered and the salt is washed with diethyl ether (100 mL). The combined organic layers are concentrated and the residue is crystallized from dichloromethane (25 mL) and hexane (100 mL) to give 3 (17.0 g. 80%) (Notes 5, 6). 

In the presence of tetrabutylammonium iodide (TBAI) in its adsorption region on the pc-Zn electrode, the edl capacitance decreased with increasing TBAI concentration and the capacity minimum shifted to more negative potentials [13]. At still more negative potentials, a well-defined adsorption- desorption peak was observed. Splitting of this peak was explained by the presence of different faces on the surface of pc-Zn electrode. 

Carbonylative cross-coupling of iodoarenes and aryl triflates with g< ///-fluorovinyltributylstannane takes place smoothly in a standard system, with triflate substrates requiring the addition of tetrabutylammonium iodide (Equation (4)). ... 

The reciprocal of the half-lifetime yielded a value for the dye regeneration by Co (dbbip)22+ of about 5 x 105 s-1 against 1.7 x 106s 1 observed in the case of 0.1 M tetrabutylammonium iodide. Contrary to the case of iodide,56 a cooperative effect of adsorbed cations was not observed in the case of cobalt, for which an addition of Li+... 

PC propylene carbonate NMO 3-methyl-2-oxazolidinone TBAI tetrabutylammonium iodide AN acetonitrile PN propionitrile GN glutaronitrile MAN methoxyacetonitrile MPN 3-methoxypropionitrile TBP tert-butylpyridine HMIml l-hexyl-3-methylimidazolium iodide DMPIml 1,2- dimethyl-3-propy-limidazolium iodide SOC Sumitomo Osaka Cement Co. Ltd. 

A mixture of benzyl-fl-i>-galactopyranoside U (1 mmol) and dibutyltin oxide (1 mmol) in benzene was refluxed for 16 b, with azeotropic removal of water. The solution was evaporated to approximately 25 mL, tetrabutylammonium iodide (1 mmol) and benzyl bromide (0.25 mL) woe added, and the mixture was refluxed for 2 h. Evaporation to... 

Treatment of methyl 4,6-0-benzylidene-2-benzyloxycarbonylamino-2-deoxy-3-0-(imidazole-l-sulfonyl)-a-D-glucopyranoside with tetrabutylammonium iodide in refluxing toluene (3 h) gave the corresponding iodo derivative in 90% yield [68] (Scheme 13). When... 

Tetrabutylammonium iodide-Boron trifluoride etherate, 287 methyl ethers... 

Sodium triacetoxyborohydride, 283 Tetrabutylammonium iodide-Boron trifluoride etherate, 287 Tributylborane, 325 Tributyl borate, 326 Triethylborane, 33, 292 Trimethyl borate, 218 Zinc borohydride, 167 Chromium Compounds Arene(tricarbonyl)chromium complexes, 19... 

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