Synthesis and rhodium complexation of enantiomerically enriched bicyclo[3.3.1]nona-2,6-diene
摘要:
Enantiomerically enriched (S,S)-bicyclo[3.3.1]nona-2,6-diene has been synthesised from the readily available diketone (S,S)-bicyclo[3.3.1]nonane-2,6-dione. The stereochemical purity is maintained on complexation to rhodium. There is a very strong preference for the formation of the homochiral over the heterochiral (alkene)(2)Rh+ 0Tf(-) complex; the self-recognition involved can be rationalised by analysis of DFT calculations. (C) 2008 Elsevier Ltd. All rights reserved.
New Ru(0)-naphthalene complexes containing a bicyclononadiene ligand catalyze the linear cross-dimerization between methyl methacrylate and substituted alkenes by an oxidative coupling mechanism. The chiral (S,S)-2-methylbicyclo[3.3.1]nona-2,6-diene complex (S,5)-1b catalyzes asymmetric linear cross-dimerization between methyl methacrylate and 2,5-dihydrofuran to give the cross-dimer In 74% yield In 80% ee.