6476-36-4Relevant articles and documents
Bis-alkynyl- and hydrido-alkynyl-osmium(II) and ruthenium(II) complexes containing triisopropylphosphine as ligand
Werner, H.,Meyer, U.,Esteruelas, M. A.,Sola, E.,Oro, L. A.
, p. 187 - 196 (1989)
The five-coordinate bis-alkynyl complexes (M=Os, Ru) have been prepared by reaction of with OsH4(CO)(P-i-Pr3)2 or MH(h2-H2BH2)(CO)(P-i-Pr3)2 (M=Os, Ru).They react with ligands L such as P(OMe)3, PMe3, CO and to giv
A Lewis Base Nucleofugality Parameter, NFB, and Its Application in an Analysis of MIDA-Boronate Hydrolysis Kinetics
García-Domínguez, Andrés,Gonzalez, Jorge A.,Leach, Andrew G.,Lloyd-Jones, Guy C.,Nichol, Gary S.,Taylor, Nicholas P.
supporting information, (2022/01/04)
The kinetics of quinuclidine displacement of BH3 from a wide range of Lewis base borane adducts have been measured. Parameterization of these rates has enabled the development of a nucleofugality scale (NFB), shown to quantify and predict the leaving group ability of a range of other Lewis bases. Additivity observed across a number of series R′3-nRnX (X = P, N; R′ = aryl, alkyl) has allowed the formulation of related substituent parameters (nfPB, nfAB), providing a means of calculating NFB values for a range of Lewis bases that extends far beyond those experimentally derived. The utility of the nucleofugality parameter is explored by the correlation of the substituent parameter nfPB with the hydrolyses rates of a series of alkyl and aryl MIDA boronates under neutral conditions. This has allowed the identification of MIDA boronates with heteroatoms proximal to the reacting center, showing unusual kinetic lability or stability to hydrolysis.
Synthesis and Crystal Structures of Copper Zinc Phenylthiolate and the First Copper Zinc Selenolate and Tellurolate Complexes
Fuhrmann, Daniel,Severin, Tobias,Krautscheid, Harald
, p. 932 - 937 (2017/08/11)
Five copper zinc phenylchalcogenolate complexes [(iPr3PCu)3(ZnMe2)2(SPh)3] (1), [(iPr3PCu)2(ZnPh)4(SPh)6] (2), [(iPr3PCu)2(ZnEt)4(SPh)6] (3), [(iPr3PCu)3(ZnEt)(SePh)4] (4), and [(iPr3PCu)3Cu(iPr3PZn)(TePh)6] (5) were synthesized by the reaction of phosphine stabilized copper phenylchalcogenolate complexes with ZnR2 (R = Me, Et, Ph) with and without additional chalcogenol. The novel mixed metal compounds were characterized by single-crystal X-ray structure analysis and NMR spectroscopy. 4 and 5 are the first examples of compounds with a Zn–Se–Cu or a Zn–Te–Cu linkage, respectively.
Structural, Kinetic, and Computational Characterization of the Elusive Arylpalladium(II)boronate Complexes in the Suzuki-Miyaura Reaction
Thomas, Andy A.,Wang, Hao,Zahrt, Andrew F.,Denmark, Scott E.
supporting information, p. 3805 - 3821 (2017/03/20)
The existence of the oft-invoked intermediates containing the crucial Pd-O-B subunit, the “missing link”, has been established in the Suzuki-Miyaura cross-coupling reaction. The use of low-temperature, rapid injection NMR spectroscopy (RI-NMR), kinetic studies, and computational analysis has enabled the generation, observation, and characterization of these highly elusive species. The ability to confirm the intermediacy of Pd-O-B-containing species provided the opportunity to clarify mechanistic aspects of the transfer of the organic moiety from boron to palladium in the key transmetalation step. Specifically, these studies establish the identity of two different intermediates containing Pd-O-B linkages, a tri-coordinate (6-B-3) boronic acid complex and a tetra-coordinate (8-B-4) boronate complex, both of which undergo transmetalation leading to the cross-coupling product. Two distinct mechanistic pathways have been elucidated for stoichiometric reactions of these complexes: (1) transmetalation via an unactivated 6-B-3 intermediate that dominates in the presence of an excess of ligand, and (2) transmetalation via an activated 8-B-4 intermediate that takes place with a deficiency of ligand.
