Iridium-catalyzed hydroiodination of functionalized alkynes

The efficiency of an Ir(I)/HI system has been studied. The association of hydroiodic acid with iridium has been tested in the catalytic hydroiodination of alkynes. The use of [Ir(cod)Cl]₂ dimer led to clean hydroiodination reactions and afforded the corresponding vinyliodides as a mixture of derivatives, where the Markovnikov type adduct was found to be the major product (80/20 to 93/7 ratio), in good yields. The mechanism was investigated and two main pathways seemed to be involved, one based on an initial oxidative addition of HI to the Ir(I) complex and the other one based on a π-activation of the alkyne moiety. The corresponding vinyliodides were engaged in Pd-catalyzed cross-coupling (Sonogashira and Suzuki-Miyaura) reactions under organoaqueuous conditions.     

(Z)-2-苯氧(硫)基甲基-2-戊烯-γ-内酯和(Z)-2-苯氧(硫)亚甲基-γ-戊内酯的简便合成

以3-苯氧(硫)基丙炔(1)为原料,经5步反应合成(Z)-2-苯氧(硫)基甲基-2-戊烯-γ-内酯(8)和(Z)-2-苯硫亚甲基-γ-戊内酯(9).合成关键步骤为TMSCl/NaI/H2O/CH3CN体系中化合物(3)的碘氢化和去共轭.     

A convenient hydroiodination of alkynes using I2/PPh3/H2O and its application to the one-pot synthesis of trisubstituted alkenes via iodoalkenes using Pd-catalyzed cross-coupling reactions

A facile hydroiodination of alkynes using readily-available reagents such as I₂, PPh₃, and H₂O has been developed. This is extended to the one-pot synthesis of trisubstituted alkenes from alkynes via iodoalkenes using Pd-catalyzed cross-coupling and related methods such as the Suzuki–Miyaura cross-coupling, Sonogashira cross-coupling reaction, and Mizoroki–Heck reaction.     

Ready access to organoiodides: Practical hydroiodination and double-iodination of carbon-carbon unsaturated bonds with I2

By using I₂ or I₂/H₃PO₃ system, various alkenes and alkynes were converted to the corresponding alkyl and alkenyl iodides in good yields. In the presence of I₂, alkynes could be di-iodinated using H₂O as the solvent in air at room temperature. This method also features the simple work-up procedure since the pure product could be obtained by extraction. Additionally, for the first time, combining with the non-toxic and cheap phosphonic acid H₃PO₃, alkenes and alkynes were also hydroiodinated successfully, which provides a simple and practical approach for synthesis of organoiodides.     

Highly regioselective hydroiodination of terminal alkynes and silylalkynes with iodine and phosphorus reagents leading to internal iodoalkenes

Markovnikov-type hydroiodination of terminal alkynes with iodine and Ph₂P(O)H took place selectively to afford the corresponding internal iodoalkenes in good yields. Combination of (PhO)₂P(O)H and Ph₂P(O)OH instead of Ph₂P(O)H also provided internal iodoalkenes in excellent yields. This hydroiodination is advantageous in terms of mild conditions, convenient operation, and tolerance to various functional groups. In addition, direct synthesis of internal iodoalkenes from silylalkynes was also achieved by using a mixed system of iodine and phosphorus reagents.     

Total synthesis of peumusolide A, NES non-antagonistic inhibitor for nuclear export of MEK

The first total synthesis of peumusolide A (1) has been achieved by combination of regio- and stereo-selective aluminum-mediated hydroiodination to 2-yn-1-ol and enantioselective reduction of 4-en-1-yn-3-one with the chiral oxazaborolidine as the key reactions. This total synthesis has unequivocally established our proposed absolute structure of 1.