297163-66-7Relevant academic research and scientific papers
Transient and Recyclable Halogenation Coupling (TRHC) for Isoflavonoid Synthesis with Site-Selective Arylation
Wan, Jie-Ping,Tu, Zhi,Wang, Yuyun
, p. 6907 - 6910 (2019)
A transient and recyclable C?H iodination has been designed for the synthesis of isoflavonoids through the domino reactions of o-hydroxyphenyl enaminones and aryl boronic acids in the presence of catalytic KI and Pd catalyst. Instead of the conventional cross-coupling strategy employing pre-halogenated substrates, this method transforms raw C?H bond by means of a transient C?H halogenation to smoothly relay the subsequent C-arylation. Consequently, such a method avoids the pre-functionalization for C?halogen bond installation as well as the generation of stoichiometric halogen-containing waste following the cross-coupled product, disclosing an intriguing new coupling protocol to forge the C?C bond in the virgin area between classical C?X (X=halogen) bond cross coupling and the C?H activation.
Stille coupling for the synthesis of isoflavones by a reusable palladium catalyst in water
Chang, Ya-Ting,Liu, Ling-Jun,Peng, Wen-Sheng,Lin, Lin-Ting,Chan, Yi-Tsu,Tsai, Fu-Yu
, p. 469 - 475 (2021/02/03)
Isoflavones were synthesized from the reaction of 3-bromochromone derivatives and aryltributylstannanes via Stille coupling catalyzed by a water-soluble and reusable PdCl2(NH3)2/2,2′-cationic bipyridyl system in aqueous solution. For prototype 3-bromochromone, the coupling reaction was performed at 80°C for 24 hr with 2.5 mol% catalyst in water in the presence of tetrabutylammonium fluoride. After the reaction, the aqueous solution could be reused for several runs, indicating that its activity was only slightly decreased. For substituted 3-bromochromones, the addition of NaHCO3 and a higher reaction temperature (120°C) were required to gain satisfactory outcomes. In addition, naturally occurring products, such as daidzein, could be obtained by this protocol via a one-pot reaction.
