The nature of the active species in bis(imino)pyridyl cobalt ethylene polymerisation catalysts.

Studies on cobalt ethylene polymerisation catalysts bearing bis(imino)pyridine ligands strongly indicate that the activated species is not the anticipated cobalt(II) alkyl cation.

Functionalized polyolefin synthesis using [P,O]Ni catalysts.

Nickel olefin polymerisation catalysts containing bulky phosphino-enolate ligands are shown to give methyl methacrylate end-functionalized polyolefins.

Asymmetric allylboration and ring closing alkene metathesis: a novel strategy for the synthesis of glycosphingolipids.

A novel strategy for the synthesis of D,L-glucosylceramide 1, a member of the glycosphingolipid class of natural products is described. Reagent-controlled asymmetric Brown allylboration gave excellent stereochemical control in the construction of adjacent stereocenters in the sphingoid base portion of the molecule. The trans-configured double bond was obtained as a single geometrical isomer by use of silicon-tethered olefin metathesis employing the Schrock carbene [(CF3)2MeCO]2Mo(=CHCMe2Ph)(=NC6H3-2,6-i-Pr2++ +) and in situ PhLi-induced ring-opening of the intermediate 5,6-dihydro-2H-1,2-oxasiline followed by protodesilylation with TBAF in DMSO. The synthesis was completed by long chain amide formation and global deprotection.