first cobalt‐catalyzed hydrogenative N‐methylation and alkylation of amines with readily available carboxylic acid feedstocks as alkylating agents and H2 as ideal reductant is described. Combination of tailor‐made triphos ligands with cobalt(II) tetrafluoroborate significantly improved the efficiency, thus promoting the reaction under milder conditions. This novel protocol allows for a broad substrate scope
Macrobicyclic triphosphazides and tri-λ5-phosphazenes derived from PhC(CH2PPh2)3. Two propeller-shaped diastereoisomers in the crystals
作者:Mateo Alajarín、Carmen López-Leonardo、José Berná、Jonathan W. Steed
DOI:10.1016/j.tet.2006.12.027
日期:2007.2
Newmacrobicyclic cage-compounds composed of two tripodal, propeller-shaped fragments linked by phosphazide and phosphazene units have been synthesized by reaction of PhC(CH2PPh2)3 with tris(m-azidobenzyl)amines. Two diastereoisomers of one of these cages have been characterized in the solid state by X-ray crystallography, one presenting two propellers with the same sense of twist P∗,P∗ whereas in