Sodium iodide-Acetonitrile

Aziridines represented by the general structure (458 X = 0, S, NR) undergo a facile ring opening and subsequent closure on heating with sodium iodide in acetone or acetonitrile. For (458 X = O) the oxazoline (460) was formed, presumably via the intermediate (459) (66JOC59). 

In a 2-1. three-necked round-bottomed flask, fitted with an efficient sealed stirrer and a reflux condenser capped by a drying tube, are placed the dried anisyl chloride (Notes 2 and 3), 73.6 g. (1.5 moles) of finely powdered sodium cyanide, 10 g. of sodium iodide, and 500 ml. of dry acetone (Note 4). The heterogeneous reaction mixture is heated under reflux with -sngorous stirring for 16-20 hours, then cooled and filtered with suction. The solid on the filter is washed with 200 ml. of acetone and discarded (Note 5). The combined filtrates are distilled to remove the acetone. The residual oil is taken up in 300 ml. of benzene and washed with three 100-ml. portions of hot water. The benzene solution is dried over anhydrous sodium sulfate for about 15 minutes, and the solvent is removed by distillation at the reduced pressure of the water aspirator (Note 6). The residual -methoxyphenyl-acetonitrile is purified by distillation under reduced pressure through an 8-in. Vigreux column b.p. 94—97°/0.3 mm. 1.5285-1.5291. The yield is 109-119 g., or 74-81% based on anisyl alcohol (Notes 7 and 8). 

Tlie starting material for this Wittig-Horner-like olefination was easily accessible by reaction of benzo-l,3-dithiolium-tetrafluoroborate with trimethylphosphite in the presence of an equimolar amount of sodium iodide in dry acetonitrile under nitrogen at room temperature (93% yield). 

The addition of diphenylmethoxyphosphane to 2,6-diphenylthiopyry-lium perchlorate (48a) in the presence of sodium iodide in acetonitrile was found to lead to isolable 4//-thiopyran 70a. The transformation 71a —> 72a proceeded analogously [90ZOB(L)1012],... 

The structurally simplest silicon reagent that has been used to reduce sulphoxides is the carbene analog, dimethylsilylene (Me2Si )29. This molecule was used as a mechanistic probe and did not appear to be useful synthetically. Other silanes that have been used to reduce sulphoxides include iodotrimethylsilane, which is selective but unstable, and chlorotrimethylsilane in the presence of sodium iodide, which is easy to use, but is unselective since it cleaves esters, lactones and ethers it also converts alcohols into iodides. To circumvent these complications, Olah30 has developed the use of methyltrichlorosilane, again in the presence of sodium iodide, in dry acetonitrile (equation 8). A standard range of sulphoxides was reduced under mild conditions, with yields between 80 and 95% and with a simple workup process. The mechanism for the reaction is probably very similar to that given in equation (6), if the tricoordinate boron atoms in this reaction scheme are replaced... 

The diimidazolide of orthophosphoric acid can again be obtained by conversion of the acid with two equivalents of CDI in acetonitrile and triethylamine. Addition of sodium iodide permits its isolation as sodium salt.[24]... 

Cyclic phosphonate analogues of hexopyranoses were debenzylated in MeOH-H20 on Pd/C. The system was purged with H2, and the reaction was run under 1 atm of H2 while being stirred vigorously. The reaction was complete after 12 hours. On the other hand, when sodium iodide in acetonitrile... 

Another variation of this method involves the treatment of an acetonitrile solution of the aryl aldehyde, trimethylsilyl chloride, and either sodium iodide, if iodide products are desired, or lithium bromide, if bromide products are desired, with TMDO. After an appropriate reaction time (5-195 minutes) at a temperature in the range of —70° to 80°, the upper siloxane layer is removed and the benzyl iodide or bromide product is isolated from the remaining lower portion after precipitation of the inorganic salts by addition of dichloromethane. For example, p-anisaldehyde reacts to form /i-rnethoxybenzyl bromide in 84% isolated yield under these conditions (Eq. 200).314,356... 

To a stirred suspension of N-(2,6-dimethyl-4-oxopyridin-l-yl)pyridin-ium tetrafluoborate (0.58 g, 2 mmol) in dry acetonitrile (20 ml) under nitrogen was added trimethyl phosphite (0.25 g, 2 mmol), followed by finely divided sodium iodide (0.30 g, 2 mmol). After 1 h at 25°C, the solvent was removed under reduced pressure, and water (20 ml) was added. The mixture was extracted with methylene chloride (3 x 15 ml), and the extracts were dried over magnesium sulfate, filtered, and evaporated under reduced pressure. The residue was dissolved in ethyl acetate (40 ml), heated at reflux for 4 h, evaporated under reduced pressure, and eluted on an alumina column (grade 1, neutral) with chloroform to yield pure dimethyl pyridin-4-ylphosphonate (0.36 g, 96%) of melting point (mp) 139 to 140°C. 

Selective reduction of a-chloro and a-bromo ketones can be achieved by treatment with sodium iodide and chlorotrimethylsilane in acetonitrile at room temperature [224],... 

When the enone 182 was heated with trimethylsilyl chloride (TMSC) and sodium iodide in acetonitrile, a mixture of the 3,1-benzoxazines 183 and 184 in a ratio of 1 5 was formed stereospecifically. The a,/3-unsaturated ketones in TMSC/Nal first gave jS-iodoketones thereafter a tertiary carbo-cation was formed, and subsequent acetonitrile addition resulted in the oxazines 183 and 184 (89TL4741). 

Glacial acetic acid. Aluminum foil. Toluene, Methylene iodide. Acetonitrile, Tetrahydrofuran, Sodium hydroxide. Acetone, Magnesium sulfate. Aluminum chloride. Chloroform Ethylenediamine, Glyoxal, Sodium nitrite. Hydrochloric acid. Nitric acid. Ethanol 4,4,4-Trinitrobutryaldehyde, Methanol, Sodium borohydride. Hydrochloric acid. Methylene chloride. Sodium bicarbonate. Magnesium sulfate... 

D. L. Chapman, for potassium tri-iodide. 0. Gropp measured the effect of temp, on the conductivity of solid and frozen soln. of sodium iodide. For the effect of press, on the electrical properties, vide alkali chlorides. A. Reis found the free energy for the separation of the ions of K1 to be 144 lrilogrm. cals, per mol. for iN al, 158 Lil, 153 and for HI, 305. S. W. Serkofi 35 measured the conductivity of lithium iodide in methyl alcohol P. Walden, of sodium iodide in acetonitrile P. Dutoit in acetone, benzonitrite, pyridine, acetophenone. J. C. Philip and H. R. Courtman, B. B. Turner, J. Fischler, and P. Walden of potassium iodide in methyl or ethyl alcohol J. C. Philip and H. P. Courtman in nitromethane P. Dutoit in acetone. H. C. Jones, of rubidium iodide in formamide. S. von Lasczynsky and S. von Gorsky, of potassium and sodium iodides in pyridine. A. Heydweiller found the dielectric constants of powdered and compact potassium iodide to be respectively 3 00 and 5 58. 

An alternative reagent is trichloromethylsilane/sodium iodide in dry acetonitrile.7613... 

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