884539-88-2Relevant academic research and scientific papers
Concave 1,10-phenanthrolines as tailored ligands for copper(I)-catalyzed diastereoselective cyclopropanations
Luening, Ulrich,Fahrenkrug, Frank
, p. 916 - 923 (2007/10/03)
Alkenyloxy-substituted aryl bridgeheads have been connected to 2,9-dichloro-1,10-phenanthroline (11) either by Suzuki coupling or by nucleophilic aromatic substitution. The resulting di- or tetraalkenes 12 or 17 have been cyclized by ring-closing metathesis to give concave 1,10-phenanthrolines 14 and 19, differing from other concave 1,10-phenanthrolines 1 in their geometries. The influence of the shapes of these ligands and those of the related concave 1,10-phenanthrolines 1a-f and 2 on the stereochemistry of the copper(I)-catalyzed cyclopropanation of indene (3) and styrene (4) has been investigated, identifying factors that favour the formation of thermodynamically less stable syn-cyclopropanes 6 and 7. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
