Selective stabilization of the anti isomer of (.eta.3-allyl)palladium and -platinum complexes

Synthesis and Properties of Tetrasubstituted 1,10‐Phenanthrolines and Their Ruthenium Complexes

“…[9][10][11] In general, 1,10-phenanthroline ligands substituted at the 2,9-and the 4,7-positions are accessible using various synthetic pathways. [12][13][14][15] However, access to phenanthrolines substituted in the 3-and 3,8-positions is rather limited and often requires tedious work up. [16][17][18][19] Tor and co-workers have shown that a multitude of different phenanthrolines can be synthesised by organometallic reactions starting from 3-bromo-and 3,8-dibromo-1,10-phenanthrolines.…”

Steric and electronic effects in stabilizing allyl-palladium complexes of “P–N–P” ligands, X2PN(Me)PX2 (X = OC6H5 or OC6H3Me2-2,6)

“…Thus, the g 3 -g 1 -g 3 isomerization step actually determines whether a given (Z)-allyl substrate will lead to retention of configuration or not in the final product. One way of controlling the g 3 -g 1 -g 3 isomerization step is to introduce a sterically bulky substituent in the auxillary ligand so that the less favourable anti-allyl palladium isomer would be stabilised [3]. Such a possibility has been realised with phenyl substituted allyl palladium complexes which adopt the less favourable syn/anti or anti/anti configuration characterised both in solid state [4] and in solution [5a].…”

“…Such a possibility has been realised with phenyl substituted allyl palladium complexes which adopt the less favourable syn/anti or anti/anti configuration characterised both in solid state [4] and in solution [5a]. However the situation becomes more challenging when the allyl moiety carries relatively small methyl groups [3].…”

A Versatile Synthesis of β‐Lactam‐Fused Oxacycles through the Palladium‐Catalyzed Chemo‐, Regio‐, and Diastereoselective Cyclization of Allenic Diols

“…In monosubstituted (h 3 -allyl)Pd complexes, the regioselectivity of the nucleophilic attack is known to be sensitive to many factors, such as steric and electronic influences from the substrate substituents, [32] regiochemical memory, [33] preferred configuration [34] and dynamic exchange in the (h 3 -allyl)Pd intermediate, [35] nucleophile, [36] and the nature of the ligands. [37][38][39] In contrast to reactions of (h 3 -allyl)Pd complexes with other nucleophiles, [40] and surpassing the regioselectivity for reactions of amines and phenols [41] or allylic fluorination, [42] a regioselective oxycyclization involving the substituted allylic carbon was obtained (Scheme 7).…”