Categories: C-I Bond Formation >
Synthesis of iodoalkynes
Acetic acid activates N-iodosuccinimide for an efficient and highly chemoselective direct iodination of terminal alkynes under metal-free conditions. This convenient process tolerates a variety of terminal alkynes and provides the desired products in very good yields.
M. Yao, J. Zhang, S. Yang, E. Liu, H. Xiong, Synlett, 2020, 31, 1102-1106.
Hypervalent iodine reagents mediate practical oxidative iodinations for the chemoselective mono-, di-, and tri-iodination of alkynes. The reaction conditions were systematically optimized by altering the iodine source and/or the hypervalent iodine reagent system.
Y. Liu, D. Huang, J. Huang, K. Maruoka, J. Org. Chem., 2017, 82, 11865-11871.
The use of chloramine-B as the oxidant and KI or NaBr as the halogen source enables a direct oxidative halogenation of terminal alkynes to provide synthetically valuable 1-iodoalkynes and 1-bromoalkynes in very good yields under mild reaction conditions.
X. Liu, G. Chen, C. Li, P. Liu, Synlett, 2018, 29, 2051-2055.
Treatment of terminal alkynes with (diacetoxyiodo)benzene, potassium iodide, and copper(I) iodide afforded 1-iodoalkynes in good to excellent yields under mild conditions.
J. Yan, J. Li, D. Cheng, Synlett, 2007, 2442-2444.
Using triethylamine as catalyst in Hunsdiecker reactions with N-halosuccinimides as Br+ or I+ source, cinnamic acids, and propiolic acids are converted to the corresponding α-halostyrenes and 1-halo-1-alkynes in good isolated yields within 1-5 min.
J. Prakash, S. Roy, J. Org. Chem., 2002, 67, 7861-7864.