Metal carbonyl complexes and chirality

A study of the Pauson-Khand reaction (PKR) based on Co-2(CO)(8) and binap has revealed that a key precatalyst is (binap)Co-2(CO)(6), and that alkynes add to this species to generate isomers that interconvert under typical PKR conditions. A P-31 NMR study of (binap)(N-(prop-2-enyl)-N-(prop-2-ynyl) -p-toluenesulfonamide)Co-2(CO)(4) revealed that heating this species gives rise to an unexpected cobalt hydride species (binap)Co(CO)(2)H together with (binap)Co-2(CO)(6). Observation of a PKR reaction by P-31 NMR spectroscopy revealed that the hydride species is generated during the course of the reaction.