533925-73-4Relevant academic research and scientific papers
Ligand tuning in asymmetric hydrovinylation of 1,3-dienes: A stereoselective route to either steroid-C20 (S) or -C20 (R) derivatives
Saha, Biswajit,Smith, Craig R.,RajanBabu
supporting information; experimental part, p. 9000 - 9005 (2009/02/03)
1,3-Dienes derived from steroidal D-ring C17-ketones undergo Ni(II)-catalyzed hydrovinylation to give 1,2- or 1,4-addition of ethylene. Using finely tuned phosphoramidite ligands, it is possible to synthesize either the C20 (R)- or (S)-derivatives without mutual contamination. The proportion of the 1,4-adduct, which is also formed stereoselectively, can be minimized by optimizing the reaction conditions. Because the two alkenes in the resultant dienes have differing steric demands for many potential reactions, and are ideally juxtaposed for further D-ring functionalization, these intermediates could be useful for the preparation of biologically important compounds such as vitamin D analogs and various antitumor steroidal glycosides.
Regio- and stereoselective ruthenium-catalyzed hydrovinylation of 1,3-dienes: Application to the generation of a 20(S) steroidal side chain
He, Zhengjie,Yi, Chae S.,Donaldson, William A.
, p. 1567 - 1569 (2007/10/03)
(Matrix presented) The addition of ethylene to 1,3-dienes and 1-vinylcycloalkenes, catalyzed by two ruthenium complexes, proceeds in a regioselective fashion to afford 3-methyl-1,4-dienes as products. For a steroidal-based 1-vinylcycloalkene, the addition
