Methyltriphenoxyphosphonium iodide,

Selective replacement of primary hydroxyl groups in carbohydrates by iodine atoms has been achieved by using the Rydon reagent, namely, methyltriphenoxyphosphonium iodide.368 Treatment of methyl 3,4-O-isopropylidene-jS-D-galactopyranoside with the phosphonium salt in benzene for 48 hours at room temperature yielded 60% of the 6-deoxy-6-iodo derivative,369 and reaction of thymidine, uridine, and 2,2 -anhydrouridine in N,N-dimethylformamide afforded 5 -deoxy-5 -iodo derivatives in yields of 63, 65, and 31%, respectively.370... 

J. P. H. Verheyden and J. G. Moffatt, Halo sugar nucleosides. I. Iodination of the primary group of nucleosides with methyltriphenoxyphosphonium iodide, J. Org. Chem. 35 2319 (1970). 

Methyltriphenoxyphosphonium iodide (3.0 g, 6.6 mmol) was added to the alcohol 56 (0.70 g, 3.2 mmol) in freshly distilled and dry MeCN (6mL). The soln was kept in the dark at rt for 24 h before dilution with Et20 and extraction with 1M NaOH. The organic layer was washed with H20 and dried (MgS04). The crude yellowish liquid obtained after solvent evaporation, which solidified after refrigeration, was purified by flash column chromatography (CH2C12/Et20 9.5 0.5) yield 0.91 g (86%). 

Primary alcohols can be reduced to hydrocarbons in two steps conversion into the iodide with triphenyl phosphite methiodide (methyltriphenoxyphosphonium iodide, 1, 1249 2. 446 ), followed by reduction with sodium cyanoborohydride in HMPT. 

With methyltriphenoxyphosphonium iodide in the presence of BF3-Et20 oxiranes are deoxygenated with retention of stereochemical integrity via the intermediate 95. ... 

Tripbenylphosphite methiodide (Methyltriphenoxyphosphonium iodide, MTPI), 1, 1249— 1250. Supplier Eastman. Commercial product can be purified to give amber-colored material by washing with ethyl acetate.1... 

The reaction of amine (91) with methyltriphenoxyphosphonium iodide (92) or (92) + I2, gave the two phosphoranes (93) and (94) respectively. X-ray crystallography revealed weak P-N interactions in both molecules, the first examples of phosphatranes containing all six-membered rings. Variable temperature NMR of (93) indicated fluxional behaviour whereby enantiomeric forms of the phos-phonium salt (chiral by virtue of clockwise and anticlockwise orientations of the propeller-shaped molecule when viewed along the C-P-N axis) interconverted rapidly at room temperature. The free energy of activation for the enantiomeric interconversion was reported to be 11.2 kcal mol compared to the isoelectronic silatrane (95) at 10.3 kcal mol. ... 

Methyltriphenoxyphosphonium iodide [1, 697, before Methyltriphenyi phosphonium bromide]. See Triphenylphosphite methiodide (1,1249). 

Methyltriphenoxyphosphonium iodide 957 Triphenyl phosphite (31 g) and methyl iodide (21 g) are heated for 36 h under reflux (exclusion of water ) the temperature of the boiling mixture rises from 70° to 115°. Addition of dry ether after cooling gives yellowish-brown needles these are repeatedly washed with dry ether and dried over phosphorus pentoxide (42 g, 94 %). For the following reactions, which must be carried out with careful exclusion of water, it is best to use a crude product that has been stored under dry ether. The iodide can, however, be purified by rapid dissolution in dry acetone and precipitation by dry ether, then having m.p. 146°.. ... 

An alternative reagent, namely pyridinium perbromide followed by butyllithium treatment has been used for this compound arising at an intermediate stage in a synthesis of the phytoalexin, orchinol. 2-(3,5-Dimethoxypheny0ethanol was converted with methyltriphenoxyphosphonium iodide in 93% yield to the iodide... 

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