50586-30-6Relevant academic research and scientific papers
Zirconium-mediated intramolecular coupling of terminal alkynes and their subsequent carbonylation: Novel synthesis of seven- and eight-membered heterocycles
Barluenga, Jose,Sanz, Roberto,Fananas, Francisco J.
, p. 1324 - 1336 (2007/10/03)
The development of a new method for the intramolecular coupling of terminal alkynes and for the synthesis of seven- and eight-membered benzoheterocyeles is reported. The key steps involve the generation of zirconocene-alkyne complexes from 2-bromoalkenes and the subsequent intramolecular carbometalation of olefins or acetylides. The 8-unsubstituted zirconabicyclopentenes were carbonylated to afford unexpected products and allow access to polyfunctionalized molecules from simple starting materials.
Intramolecular Heck-type reactions in aqueous medium. Dramatic change in regioselectivity
Lemaire-Audoire, Sandrine,Savignac, Monique,Dupuis, Christophe,Genet, Jean-Pierre
, p. 2003 - 2006 (2007/10/03)
Efficient intramolecular Heck-type cyclizations were carried out in aqueous medium using water-soluble Pd/TPPTS catalysts. Under these conditions, the generally observed exo process was reversed in favor of the regioselective formation of endo cyclized co
Electrocatalytic Coupling of Aryl Halides with (1,2-Bis(di-2-propylphosphino)benzene)nickel(0)
Fox, Marye Anne,Chandler, Daniel A.,Lee, Changjin
, p. 3246 - 3255 (2007/10/02)
Dibromo- and dichloro(1,2-bis(di-2-propylphosphino)benzene)nickel(II) is compared with tetrakis(triphenylphosphino)nickel(II) as an electrocatalyst for the reductive coupling of aryl halides.In many of the reactions examined, dehalogenation of the substrate predominated over coupling; however, preparative yields of biphenyls as high as 96percent can be obtained with aryl chlorides and 2 mol percent of the title catalyst in polar, coordinating solvents.Experimental factors governing the efficiency of these reactions are discussed, and possible mechanisms for coupling and catalyst deactivation are considered.Much better selectivity for aryl chlorides is attained in electroreductive couplings catalyzed by the title compound, whereas electrocatalysis with (Ph3P)4NiCl2 allows for selective intra- and intermolecular coupling at aryl bromide and vinyl chloride sites.Modest yields of cyclization products can be attained with either electrocatalyst in the presence of appropriately functionalized aryl or vinyl halides.
