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Synthesis of α-iodocarboxylic acids and derivatives

Recent Literature

By rendering the α-position of amides electrophilic through a mild and chemoselective umpolung transformation, a broad range of widely available oxygen, nitrogen, sulfur, and halogen nucleophiles can be used to generate α-functionalized amides.
C. R. Gonçalves, M. Lemmerer, C. J. Teskey, P. Adler, D. Kaiser, B. Maryasin, L. González, N. Maulide, J. Am. Chem. Soc., 2019, 141, 18437-18443.

Primary, secondary, tertiary, benzylic, propargylic and α-functionalized alkyl fluorides react in chlorinated or aromatic solvents at room temperature or upon heating with inexpensive lithium iodide to give the corresponding iodides in very good yields. The reaction is selective for aliphatic monofluorides and can be coupled with in situ nucleophilic iodide replacements.
K. Balaraman, S. Kyriazakos, R. Palmer, F. Y. Thanzeel, C. Wolf, Synthesis, 2022, 54, 4320-4328.

γ-Hydroxy-α,β-acetylenic esters are used as precursors for the preparation of γ-hydroxy-α,β-alkenoic esters by means of trans-selective additions of two hydrogen atoms or one hydrogen atom and one iodine atom across the triple bonds. These methods allow the preparation of β-substituted and α,β-disubstituted alkenoic esters in highly stereoselective manners.
C. T. Meta, K. Koide, Org. Lett., 2004, 6, 1785-1787.


Treatment of widely available isocyanates with monohalolithium and dihalolithium carbenoids provides α-halo- and α,α-dihaloacetamide derivatives. While monohalolithium carbenoids can be prepared by a smooth lithium-halogen exchange, the preparation of the corresponding dihalo compounds proved to be highly dependent on the base used to realize the deprotonation, with lithium 2,2,6,6-tetramethylpiperidine emerging as optimal.
V. Pace, L. Castoldi, A. D. Mamuye, W. Holzer, Synthesis, 2014, 46, 2897-2909.