Methyl iodide, with triphenyl phosphite

The aHphatic iodine derivatives are usually prepared by reaction of an alcohol with hydroiodic acid or phosphoms trHodide by reaction of iodine, an alcohol, and red phosphoms addition of iodine monochloride, monobromide, or iodine to an olefin replacement reaction by heating the chlorine or bromine compound with an alkaH iodide ia a suitable solvent and the reaction of triphenyl phosphite with methyl iodide and an alcohol. The aromatic iodine derivatives are prepared by reacting iodine and the aromatic system with oxidising agents such as nitric acid, filming sulfuric acid, or mercuric oxide. 

Triphenyl phosphite, with methyl iodide and cyclohexanol,... 

Cyclohexanediol, from hy-droquinone, 51, 105 Cyclohexanol, with triphenyl phosphite and methyl iodide,... 

The phosphorus activation of alcohols to substitution with inversion of configuration. The reactions are based on the high heat of formation of the P-O bond and the tendency for phosphorus to form multiple bonds with oxygen. For example, treatment of an alcohol with triphenyl phosphite and methyl iodide leads to the corresponding iodo compound (Scheme 2.17). 

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. 

One might expect that a phosphorus reagent having for R an aryl group activated for bimolecular nucleophilic substitution (68) by electron- withdrawing substituents might participate in a Michaelis-Arbuzov reaction. Kamai and Koshkina (159), who prepared a number of chloro-and nitro-substituted derivatives of triphenyl phosphite, found this to be the case for both ortho and para isomers of tris(monochlorophenyl) phosphite, which reacted with alkyl halides to furnish phosphonates. On the other hand, tris(2,4,6-trichlorophenyl) phosphite and tris(2,4-dichlorophenyl) phosphite (155) gave only complexes with methyl iodide however, lower reaction temperatures were employed. 

Methylenecyclopropanes, 50, 30 3-Methylheptan-4-ol, 52, 22 Methyl iodide, with triphenyl phosphite and cyclohexanol,... 

A. Neopentyl iodide. A 500-ml. two-necked round-bottomed flask is fitted with a reflux condenser to which is attached a calcium chloride drying tube. One hundred thirty-six grams (115 ml., 0.44 mole) of triphenyl phosphite, 35.2 g. (0.4 mole) of neopentyl alcohol, and 85 g. (37 ml., 0.60 mole) of methyl iodide (Note 1) are added to the flask, and a thermometer is inserted that is of sufficient length to extend into the liquid contents of the flask. The mixture is heated under gentle reflux... 

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... 

Preparation. Verheyden and Moffatt have introduced some improvements in the original preparation of Landauer and Rydon (1, 1249-1250, ref. 1). Triphenyl phosphite (0.2 mole) and methyl iodide (0.26 mole) are placed in a 90° oil bath and the temperature of the bath is slowly raised to 125° over 8 hr. The pot temperature rises slowly from 70 to 85° and then rapidly to 115°. This temperature is maintained for 12 14 hr. upon cooling and seeding, the mixture crystallizes to a soUd brown mass. Dry ether is added the resulting material is repeatedly washed by decantation with fresh dry ethyl acetate. The reagent is obtained as amber crystals in 90% yield. The reagent should be handled in a dry box under nitrogen. 

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. 

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