Tridentate phosphine ligands with novel linker-units

Functionalized Tri‐ and Tetraphosphine Ligands as a General Approach for Controlled Implantation of Phosphorus Donors with a High Local Density in Immobilized Molecular Catalysts

“…The lack of supported polyphosphines reported in the literature might be attributed to the challenging requirements for the selective and efficient functionalization of the backbone of such sophisticated ligands. [13] Indeed, the introduction of phosphino groups at an early stage of the design sequence renders subsequent modifications much more difficult. Protection and deprotection procedures for phosphorus donors might be necessary, and the loss of phosphine during the overall process could be considerable.…”

“…When impurities were still present, purification by flash column chromatography on silica gel (eluent: AcOEt/heptane 1:4) was performed to yield 7 (3.2 g, 50 %) as an orange-red powder. 1 31 P{ 1 H} NMR (CDCl 3 , 242.9 MHz): d = À30.4 (AA' spin system, 2 P), À34.4 ppm (BB' spin system, 2 P); 13 Owing to the reactivity of the formyl function, proper mass analyses were not obtained.…”

Novel N,N,O Scorpionate Ligands and Transition Metal Complexes Thereof Suitable for Polymerisation

“…[12] Recently, we have been successful in introducing linking groups such as allyl and hydroxymethyl to the bridging carbon atom of 1 suitable for solid-phase fixation of bis(3,5-dimethylpyrazol-1-yl)acids and manganese and rhenium tricarbonyl complexes thereof. [15] Solid-phase-grafted ligands are not only of interest due to the advantages of supported catalysts in potential applications, [16][17][18][19] but to prevent the formation of bisligand complexes without the need of sterically demanding substituents, as well. Polymerisation-active linking groups allow a cheaper synthesis and a more detailed control of the resulting solid than modifications of commercially available solid phases, concerning the degree of functionalisation and the structure of the surrounding solid phase.…”

Phosphines and Related Tervalent Phosphorus Systems

“…161 Metallophosphide routes have been applied to the preparation of a wide range of di-, tri-and tetra-phosphines bearing additional donor or other reactive functional groups. Findeis and Gade have described the synthesis of a series of di-and triphosphines bearing alkenyl, alkynyl 162,163 and hydroxyalkyl groups, 164 e.g., (82), these acting as linkers for the synthesis of phosphino-functional dendrimers and related catalyst systems. Various chiral oxo-and oxy-functional diphosphines, e.g., (83), have been prepared from the camphor system.…”