1027409-95-5Relevant academic research and scientific papers
Highly regioselective internal heck arylation of hydroxyalkyl vinyl ethers by aryl halides in water
Arvela, Riina K.,Pasquini, Serena,Larhed, Mats
, p. 6390 - 6396 (2008/02/10)
(Chemical Equation Presented) Highly regioselective and fast Pd(0)-catalyzed internal α-arylation of ethylene glycol vinyl ether with aryl halides was shown to be possible in water without the need for any halide scavengers or ionic liquid additives. This presents, to our knowledge, the first case of water being utilized in the selective arylation of electron-rich olefins. Resulting α-products were hydrolyzed and isolated as corresponding acetophenones in good to excellent yields when using aryl bromides and with good to moderate yields in the case of aryl iodides. Microwave irradiation was shown to be beneficial in activation of aryl chlorides toward the internal Heck arylation. The scope of the protocol was further increased to include different hydroxyalkyl vinyl ethers, these all giving selectively only branched α-products. Finally, the active role of the hydroxy group in directing the regioselectivity toward internal arylation of electron-rich olefins, even in nonpolar toluene, was revealed.
Direct synthesis of protected arylacetaldehydes by tetrakis(phosphane)- palladium-catalyzed arylation of ethyleneglycol vinyl ether
Kondolff, Isabelle,Doucet, Henri,Santelli, Maurice
, p. 765 - 774 (2007/10/03)
A range of aryl bromides undergo Heck reaction with ethylene glycol vinyl ether, in the presence of [PdCl(C3H5)]2/ cis,cis,cis-1,2,3,4-tetrakis[(diphenylphosphanyl)methyl]cyclopentane as catalyst, to give regioselectively protected arylacetaldehydes in good yields. The β-arylation products were obtained in with 93-100 % selectivity with electron-poor aryl bromides or heteroaryl bromides. Furthermore, this catalyst can be used at low loading, even for reactions with sterically hindered aryl bromides. The aryl vinyl ether intermediates undergo subsequent ketalisation to give the corresponding 2-benzyl-1,3-dioxolane derivatives. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
