Alternating ring-opening copolymerization (ROCOP) is a versatile synthetic method for preparing polyesters using relatively inexpensive and readily available monomers, epoxides and cyclic anhydrides. In this study, a new type of titanium (IV) complex coordinated with iminophenolate ligands was developed as an efficient catalyst for alternating ROCOP. As found in the crystal structures, iminophenolate titanium (IV) complexes exhibited octahedral geometries owing to geometrical con-straints. Electronic tuning of iminophenolate ligands revealed that chloro-substituted ligands are more efficient than other ligands with electron-withdrawing or electron-donating ligands. Density functional theory computation provided reaction profiles where octahedral intermediates and transition states were stabilized, and the chlorine substituent was the most efficient in stabilizing the transition state for the epoxide opening step.

The reductive cross-coupling of terminal alkenes and N-heterocyclic bromides has been demonstrated by ligand optimization of Pd and CuH catalysis. The optimized ligands are Briphos, a π-acceptor monodentate phosphorus ligand,...

Novel P,O-type ligands, N-disulfonyl bicyclic bridgehead phosphorus triamides, were synthesized and utilized in Pd-catalyzed hydrosilylation involving tertiary silanes, unactivated alkenes, and conjugated dienes. The ligand displayed a remarkable level of reactivity for alkene hydrosilylation with tertiary silanes and its use resulted in a significant improvement in the regioselectivity of diene hydrosilylation towards 1,2-hydrosilylation. X-ray crystallographic analysis confirmed the bidentate nature of the ligand, with coordination of phosphorus and oxygen. Control experiments provided evidence for the formation of Pd 0 species and the reversibility of PdÀ H insertion in the reaction mechanism. Density functional theory (DFT) computations supported the importance of the hemilabile P,O ligand in stabilizing both the rate-determining transition state of PdÀ H insertion and the transition state of reductive elimination that determines the regioselectivity.

Novel P,O‐type ligands, N‐disulfonyl bicyclic bridgehead phosphorus triamides, were synthesized and utilized in Pd‐catalyzed hydrosilylation involving tertiary silanes, unactivated alkenes, and conjugated dienes. The ligand displayed a remarkable level of reactivity for alkene hydrosilylation with tertiary silanes and its use resulted in a significant improvement in the regioselectivity of diene hydrosilylation towards 1,2‐hydrosilylation. X‐ray crystallographic analysis confirmed the bidentate nature of the ligand, with coordination of phosphorus and oxygen. Control experiments provided evidence for the formation of Pd0 species and the reversibility of Pd−H insertion in the reaction mechanism. Density functional theory (DFT) computations supported the importance of the hemilabile P,O ligand in stabilizing both the rate‐determining transition state of Pd−H insertion and the transition state of reductive elimination that determines the regioselectivity.