Novel synthesis of gem-dimetalloalkanes containing boron and germanium

ORGN 134

Narayan G. Bhat, nbhat@panam.edu, Department of Chemistry, University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78541 and Elvis A. Cavazos, Chemistry, University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78541.
A convenient, novel synthesis of gem-dimetalloakanes containing boron and germanium based on the α-bromoalkyllboronate esters is developed. Alpha-bromoalkylboronate esters readily available from literature procedures smoothly undergo a reaction with freshly generated trimethylgermyllithium in hexamethylphosphoramide (HMPA) at -78 oC to provide the corresponding tetracoordinated boron complexes. These boron complexes undergo intramolecular nucleophilic substitution reaction to provide the corresponding alkylboronate esters containing trimethylgermyl moiety. These intermediates are isolated in good yields (72%-84%) and are characterized by the spectral data (PMR and CMR).