Iodides, from alcohols, methyl iodide, and triphenyl phosphite

Indole, sodium salt, preparation of, 54, 60 Indole, 1-benzyl, 54, 50, 58 Indoles, iV-alkyl-, 54, 58, 60 Iodides, from alcohols, methyl iodide, and triphenyl phosphite, 51, 47 ... 

Methylcyclohexene, from 2-methyl-cyclohexanone tosylhydrazone and methyllithium, 51,69 Methylenecyclopropanes, 50,30 Methyl iodide, with triphenyl phosphite and cyclohexanol, 51,45 with triphenyl phosphite and neopentyl alcohol, 51,44 METHYL ftrans-2-IODO-l-TETRA-LIN)CARBAMATE, 51,112 Methyl (frans-2-iodo-l-tetralin)carba-mate, with potassium hydroxide to give 1,2,3,4-tetrahydronaph-thalene(l,2)imine, 51,53 Methyllithium, with camphor tosylhydrazone to give 2-bomene, 51, 66... 

Iodoallenes are prepared from propargyl alcohols by means of phosphonium iodide produced in situ from triphenyl phosphite and methyl iodide. In addition, small amounts of the isomeric iodoacetylenes are formed in this process. 

Phosphite diiodide converts alcohols to iodides. This reagent has been used much less often than the corresponding dibromides or dichlorides. Phosphite methiodides give better yields of iodides in the reaction with primary, secondary and tertiary alcohols and are simple to use. Neopentyl iodide is isolated in 70% yield from the reaction of triphenyl phosphite, neopentyl alcohol and methyl iodide (equation 25). This reaction is remarkable considering the severe steric bulk of the neopentyl group which often makes rearrangement become the major process. 

Direct preparation of an alkyl iodide by reaction (a) neopentyl iodide, (CH3)3CCH2I 957,958 Methyl iodide (1.4 moles), triphenyl phosphite (1 mole), and neopentyl alcohol (1 mole) are heated in a bath for 24 h, whereby, owing to continuing consumption of methyl iodide, the internal temperature rises from 75° to 130°. The crude iodide and the phenol are distilled off in a vacuum and the distillate is washed with ice-cold, dilute NaOH solution, and water until free from phenol. The product contains about 6% of te/7-pentyl iodide,958 to remove which it is shaken for 5 h with three times its volume of water which is then discarded. The organic layer is next shaken with its own volume of O.lN-aqueous AgN03, washed with water, dried, and fractionated. This gives a 53-57% yield of iodide of b.p. 71°/100 mm. 

Michaelis and Kaehne isolated a product with saltlike properties from the reaction of triphenyl phosphite and methyl iodide. This observation has been confirmed by Arbuzov and Sazonova (30) and by Landauer and Rydon (206,284), who used this salt as a reagent for the preparation, in excellent yields, of alkyl halides, including neopentyl iodide, from the corresponding alcohols. The course of this reaction... 

A related procedure involves heating the alcohol with an adduct formed from triphenyl phosphite and methyl iodide.In this instance a reactive alkoxyphosphonium intermediate is formed by displacement of a phenoxy group at phosphorus. 

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