Neopentyl alcohol, with triphenyl

Neopentyl alcohol, with triphenyl phosphite and methyl iodide, 51,44 NEOPENTYL IODIDE, 51,44 Nickel carbonyl, precautions for handling, 52,117... 

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... 

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... 

Following a comparison of the behaviours of trialkyl phosphites, mixed alkyl phenyl phosphites and triphenyl phosphite towards iodomethane and, in the last case, the breakdown of the phosphonium salt when treated with an alcohol, Landauer and Rydon considered that all the reactions involve a stage identical with that of the normal Michaelis-Arbuzov reaction. The absence of any rearrangement during the decomposition of complexes from neopentyl phosphites, and the configurational inversion which occurs when optically active 2-halooctanes are produced from optically active phosphite triesters (themselves obtained from optically active octan-2-ol), suggest that the mode of breakdown of the intermediate complexes is of S 2 character. 

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