CARBENE COMPLEXES XIX. OPTICALLY ACTIVE ELECTRON-RICH OLEFIN-DERIVED CARBENE-TRANSITION-METAL COMPLEXES. CRYSTAL STRUCTURES OF , , AND

Article abstract of DOI:10.1016/0022-328X(85)80348-X

Several optically active electron-rich olefins L₂^* have been prepared from readily available chiral starting materials, such as (S)-α-amino-acids (e.g., (S)-leucine) or terpene derivatives (e.g., (+)- or (-)-3-pinanecarboxylic acid).The derived carbene-transition-metal complexes (17 monocarbene Rh^I, 1 bis(carbene)Rh^I, and a d⁸ Co complex) have been prepared with retention of optical integrity; some of their chemical and spectroscopic properties are described.X-Ray structures of four transition-metal complexes bearing optically active carbene ligands (L^*) derived from (S)-proline, (R)-(-)-trans-N,N'-dimethyl-1,2-diaminocyclohexane, (S)-leucine, or (S)-alanine, respectively are also reported: cis*Me)>, cis-*Me)>, trans-iL^*Me)(PPh3)2>, and *Me)(NO)(PPh3)>.