Lodine/Pyridine

Iodine, 72, 293-295, 333, 452,579 Iodine-Dimethyl sulfoxide, 295 Iodine-Potassium iodate, 296 Iodine-Pyridine N-oxide, 296 lodine-Pyridine-Sulfur dioxide, 296 Iodine azide, 297 Iodine bromide, 297 lodoacetonitrile, 494 a-lodo acyl chlorides, 116 o-Iodoanisole, 130 lodobenzene, 130, 443 7r-(Iodobenzene)chromium tricarbonyl, 104 lodobenzene diacetate-Trimethylsilyl azide, 297... 

Fig. 16 lodination of 4-pentenoic acid and 4-penten-l-ol with iodine/pyridine or di-4-chlorophenyltellurium(IV) diiodide (5)/pyridine. 

Lastly, a formal synthesis of almotriptan (5) has been published by the Bosch group in Spain using an intramolecular Heck approach (Scheme 23). lodination of aniline 58 with bis(pyridine)iodonium(I) tetrafluoroborate followed by reaction with trifluoroacetic anhydride (TFAA) gave the o-iodotrifluoroacetanilide 66. Alkylation of 66 with methyl 4-bromocrotonate afforded 67, which underwent palladium catalyzed... 

Anhydrous Hydrogen Fluoride in Pyridine Containing A -Bromosuccinimide, N-Iodosuccinimide, lodine/Silver Nitrate, or Bromine/Silver Nitrate, Followed by Silver(l) Fluoride... 

Iodine pentafluoride (28) in hot pyridine works like LTA as a Hofmarm reagent for aliphatic primary carboxamides (equation 21). lodination occurs together with rearrangement when benzamide is treated under similar reaction conditions. 

Bis(pyridine)iodine(I) tctr lodinations. Good >1 from the parent enaminooe peptides with this reagent 1 Reaction with alkynes. simultaneously introducing sulfides undergo cyclizatkx... 

The electrophilic aromatic substitution of the pyridine ring continues to be explored as a way to prepare substituted pyridines. Bw-( 5y w-collidine)-iodine(I) and bromine (I) are effective iodinating or brominating agents, respectively, of pyridinols, although the di- or tri-halogenated products are obtained <97TL2467>. lodination of 3-pyridinol produces 5-hydroxy-... 

As detailed in Scheme 1, the intramolecular Heck approach began by protecting para-chlorophenylethylamine (9) as its corresponding trifluoroacetamide 10. lodination of 10 may be achieved in couple of alternatives either with iodine monochloride or with its more sophisticated cousin bis(pyridine)iodonium(I) tetrafluoroborate to furnish iodide 11. Iodide 11 was aUylated to afford 12, which underwent an intramolecular Heck... 

Methyl-3-pyridinol is brominated in pyridine to give 2-bromo- and then 2,4-dibromo-6-methyl-3-pyridinol. lodination with sodium iododichloride gives 2-iodo-6-methyl-3-pyridinol. lodination of 2-(/7-substituted phenyl)-3-pyri-dinols (Xn-665 R = H, CHj, C Hs, CH(CH3)2. C(CH3)3, Q, OCHj) gives 2-aiyl-6-iodo-3-pyridinols. This should be contrasted with nitration of these pyridinols, which occurs first on the phenyl group " (Section II1.2.D.,... 

C. lodinating Agents Bis(pyridine)iodonium tetrafluoroborate Selective iodination and iodocyclization... 

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