1209496-07-0Relevant academic research and scientific papers
Palladium-catalyzed cross-coupling reaction of heteroaryltriolborates with aryl halides for synthesis of biaryls
Yamamoto, Yasunori,Takizawa, Miho,Yu, Xiao-Qiang,Miyaura, Norio
, p. 359 - 368 (2010)
Cyclic triolborates possessing a heteroaromatic ring on the boron atom [ArB(OCH2)3CHCH3]M (M=K, Na, Li) were prepared in high yields from heteroarylboronic acids, 1,1,1-tris(hydroxymethyl)ethane (triol) and KOH or NaH. The corresponding lithium salts were synthesized from aryllithiums, B(OMe)3 and triol. They were air-stable white solids that were convenient for handling in air. High performance of these triolborates for metal-catalyzed bond-forming reactions was demonstrated in palladium-catalyzed cross-coupling reactions with haloarenes. Although the use of heteroarylboronic acids often results in very low yields due to competitive hydrolytic B-C bond cleavage with water under typical conditions using aqueous bases, triolborates possessing a 2-pyridyl, 3-pyridyl or 2-thiophenyl ring afforded biaryls in high yields at 50-120C in anhydrous DMF. There was a strong accelerating effect of CuI for reactions of 2-and 3-pyridylborate derivatives, whereas 2-thiophenyl derivatives reacted smoothly resulting in high yields in the absence of CuI.
Novel synthesis of 6-substituted 2-picolines from aryl/heteroaryl β-enaminones and meldrum's acid using cecl3.7H2o/nai
Addla, Dinesh,Kantevari, Srinivas
, p. E384-E388 (2014/11/08)
One-pot condensation of aryl/heteroaryl β-enaminones, Meldrum's acid, and ammonium acetate in the presence of CeCl3.7H2O/NaI via tandem Michael addition-cyclodehydration-elimination sequence led to the formation of novel regioselecti
