Boron Trihalide Mediated Alkyne-Aldehyde Coupling Reactions: A Mechanistic Investigation
作者:George W. Kabalka、Min-Liang Yao、Scott Borella、Zhongzhi Wu、Yu-Hong Ju、Travis Quick
DOI:10.1021/jo702493j
日期:2008.4.1
A borontrihalide mediated alkyne-aldehyde coupling reaction leading to stereodefined 1,3,5-triaryl-1,5-dihalo-1,4-pentadienes is described. The study led to the discovery of a direct substitution of hydroxyl groups by stereodefined alkenyl moieties using alkenylboron dihalides. During the investigation, it was also discovered that, at low temperatures, the reaction of BCl3 with alkynes produces monovinylboron
Fe powder catalyzed highly efficient synthesis of alkenyl halides via direct coupling of alcohols and alkynes with aqueous HX as exogenous halide sources
作者:Yong-Rong Yang、Qiang Zhang、Feng-Tian Du、Jian-Xin Ji
DOI:10.1016/j.tet.2015.04.065
日期:2015.6
A simple and efficient catalytic method for the synthesis of alkenylhalides via direct coupling of alcohols and alkynes using aqueous HX (X=Cl, Br) as halide sources has been developed under mild conditions in the presence of Fe powder (1 mol %). In comparison with the high loading of FeX3 in previously reported protocols, the present approach provides a remarkable attractive methodology to a diverse
New and Efficient Iron Halide Mediated Synthesis of Alkenyl Halides through Coupling of Alkynes and Alcohols
作者:Srijit Biswas、Sukhendu Maiti、Umasish Jana
DOI:10.1002/ejoc.200900104
日期:2009.5
simple, and straightforward one-pot reaction of alkynes with various alcohols in the presence of iron salts (FeCl3 and FeBr3) was described to yield the corresponding alkenyl halides with complete regioselectivity and highstereoselectivity. The reaction is high yielding and works under mild conditions. The iron salts act as Lewis acids and a source of halides. The reaction tolerates a wide variety of functional
Titanium(IV) Halide Mediated Coupling of Alkoxides and Alkynes: An Efficient and Stereoselective Route to Trisubstituted (<i>E</i>)-Alkenyl Halides
作者:Min-Liang Yao、Travis R. Quick、Zhongzhi Wu、Michael P. Quinn、George W. Kabalka
DOI:10.1021/ol900669t
日期:2009.6.18
Alkoxide C-O bond cleavage occurs readily at room temperature in the presence of titanium(IV) halide. Capture of the resultant carbocation by alkynes provides an efficient route to trisubstituted (E)-alkenyl halides with high stereoselectivity.
Iron-Promoted Synthesis of Substituted 1-Halo-1,4-pentadienes by Reaction of 1,3-Diarylpropenes with Ethynylbenzenes via sp<sup>3</sup> C−H Bond Activation
作者:Hanjie Mo、Weiliang Bao
DOI:10.1021/jo1006398
日期:2010.7.16
An iron-promoted sp3 C−H bond activation and C−C bond formation reaction between 1,3-diarylpropenes and ethynylbenzenes was realized with BQ (benzoquinone) as an oxidant. The reaction afforded 1-halo-1,4-pentadiene derivatives in moderate to good yields under mild conditions.