Highly diastereoselective synthesis of (Z)-1-trimethylgermyl-1-alkenes

ORGN 629

Narayan G. Bhat, nbhat@panam.edu, Department of Chemistry, University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78541 and Maria M. Villarreal, Department of Chemistry, The University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78541.
The reagent system Cp2ZrCl2/2EtMgBr (prepared by adding EtMgBr to a solution of Cp2ZrCl 2 in tetrahydrofuran at -78 oC for 3 h) converts 1-trimethylgermyl-1-alkenes (easily prepared by the reaction of 1-alkynyllithium with trmethylgermanium bromide) into alpha-trimethylgermylzirconacyclopentenes at. -78 oC for 1 h followed by stirring at room temperature overnight. These novel intermediates are hydrolyzed at 0 oC for an hour to provide the corresponding (Z)-1-trimethylgermyl-1-alkenes in good yields (74%-85%) and in high stereochemical purities (>98%) as evidenced by 13C spectral data.
 

Materials, Devices and Switches, Metal-Mediated Reactions, Asymmetric Reactions, Total Synthesis, Biologically-Related Molecules and Processes
7:00 PM-9:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- La Louisiane, Blrm. C, Poster

Division of Organic Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008