3875-77-2Relevant articles and documents
A novel and direct synthesis of chroman derivatives using a hypervalent iodine(III) reagent
Hamamoto, Hiromi,Hata, Kayoko,Nambu, Hisanori,Shiozaki, Yukiko,Tohma, Hirofumi,Kita, Yasuyuki
, p. 2293 - 2295 (2004)
The direct aromatic carbon-oxygen bond-formation reaction was described and the novel and simple synthetic method for chroman derivatives involving aromatic cation radical intermediates was developed using the hypervalent iodine(III) reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA).
Nickel-mediated inter- and intramolecular reductive cross-coupling of unactivated alkyl bromides and aryl iodides at room temperature
Yan, Chang-Song,Peng, Yu,Xu, Xiao-Bo,Wang, Ya-Wen
, p. 6039 - 6048 (2012/06/18)
A nickel-mediated intermolecular reductive cross-coupling reaction of unactivated alkyl bromides and aryl iodides at room temperature has been developed and successfully extended to less explored intramolecular versions and tandem cyclization-intermolecular cross-coupling. Highly stereoselective (or stereospecific) synthesis of linear-fused perhydrofuro[2,3-b]furan (pyran) and spiroketal skeletons allows rapid access to these useful building blocks, which would be potentially valuable in the synthesis of relevant natural products. A rational explanation for the formation of contiguous stereogenic centers is given. Copyright
Intramolecular hydroarylation of alkynes catalyzed by platinum or gold: Mechanism and endo selectivity
Nevado, Cristina,Echavarren, Antonio M.
, p. 3155 - 3164 (2007/10/03)
The cyclization of differently substituted aryl alkynes with Pt II or AuI catalysts proceeds by endo-dig pathways. When AgI was used to generate reactive cationic AuI catalysts, 2H-chromenes dimerize to form cyclobutane derivatives by a Ag I-catalyzed process. A DFT study on the cycliza-tion mechanism shows a kinetic and thermodynamic preference for 6-endodig versus 5-exo-dig cyclizations in PtII-catalyzed processes. Calculations indicate that although Friedel-Crafts and the cyclopropanation processes via metal cyclopropyl carbenes show very similar activation energies, platinum cyclopropyl carbenes are the stationary points with the lowest energy.
