An unprecedented Pd(II)-catalyzed decarbonylative C–H/C–C activation and annulationreaction, which proceeds via intramolecular cyclization, is reported. This reaction of hydroxynaphthoquinones with disubstituted alkynes provides good yields of substituted alkylidene phthalides, which are the key intermediates for the synthesis of bioactive natural products.
A Highly efficient route for the synthesis of 1,2-disubstituted acetylene derivatives has been developed by palladium catalyzed cross-couplings of alkynyl halides with (hetero)aryl aluminium reagents under mild conditions. This has given corresponding cross-coupling products good to excellent isolated yields of up to 99%. The aryls bearing electron-donating or electron-withdrawing groups in either
Synthesis of Fused 4-Iodoselenophene[2,3-<i>b</i>]thiophenes by Electrophilic Cyclization of 3-Alkynylthiophenes
作者:André L. Stein、Juliana da Rocha、Paulo Henrique Menezes、Gilson Zeni
DOI:10.1002/ejoc.200901118
日期:2010.2
We present here our results on the electrophilic cyclization reaction of 3-alkynylthiophenes with different electrophiles such as I 2 , ICl, and PhSeBr. The cyclization reaction proceeded cleanly under mild reaction conditions, giving fused 4-iodoselenophene[2,3-b]thiophenes in excellent yields. In addition, the obtained chalcogenophenes were readily transformed into more complex products through palladium-
我们在此展示了 3-炔基噻吩与不同亲电试剂(如 I 2 、ICl 和 PhSeBr)的亲电环化反应的结果。环化反应在温和的反应条件下顺利进行,以优异的产率得到稠合的 4-碘硒吩[2,3-b]噻吩。此外,通过钯或铜催化与硫醇、硼酸和有机锌试剂的交叉偶联反应,获得的硫属元素很容易转化为更复杂的产物。
Cross‐Coupling Between Aryl Halides and Aryl Alkynes Catalyzed by an Odd Alternant Hydrocarbon
作者:Swagata Sil、Anattil Unnikrishnan Krishnapriya、Pallabi Mandal、Rositha Kuniyil、Swadhin K. Mandal
DOI:10.1002/chem.202400895
日期:2024.6.6
hydrocarbon based on phenalenyl unit acts as a catalyst for cross-coupling between arylhalides and arylalkynes synthesizing a rich library of internal alkynes without any external stimuli. This protocol was extended to accomplish the Sonogashira-type couplingunder transition-metal-free and solvent-free conditions.