Synthesis of Water-Soluble, Aliphatic Phosphines and Their Application to Well-Defined Ruthenium Olefin Metathesis Catalysts

Abstract

Water-soluble aliphatic phosphines Cy 2 P(CH 2 ) 2 N(CH 3 ) 3 + Cl -(14), Cy 2 P[4-(N,N-dimethylpiperidinium)] + Cl -(15), Cy 2 P(CH 2 ) 2 SO 3 -Na + (16), and CyP[(CH 2 ) 2 N(CH 3 ) 3 + Cl -] 2 (17) (Cy ) cyclohexyl) were prepared from air-stable, borane-protected precursors. Spectroscopic investigations of corresponding Pd(PR 3 ) 2 Cl 2 complexes were used to estimate the steric parameters of these new phosphines. Spectroscopic investigation of Ni(CO) 3 PR 3 complexes of the new phosphines indicated that phosphines bearing quaternary amine functionalities were less electron donating than tricyclohexylphosphine, while the presence of a sulfonate group increased phosphine electron donation. Cationic phosphines 14 and 15 were used to synthesize water-soluble ruthenium carbene complexes of the type (Cy 2 PR) 2 Cl 2 RudCHPh. These complexes initiate the ring-opening metathesis polymerization (ROMP) of functionalized 7-oxanorbornenes in water, methanol, and aqueous emulsions.

(Dicyclohexylphosphino)borane, BH3PH(C6H11)2, a Precursor to Water-Soluble Phosphine Ligands

“…Our interest in this compound is based on its widespread use as an intermediate in the synthesis of cationically and anionically functionalized water-soluble phosphines (Mohr, Lynn & Grubbs, 1996). Figs.…”

Aqueous Olefin Metathesis

“…Although alkylidene 50 is soluble in water, it did not initiate ROMP in aqueous solution. In further studies, the same research group prepared the watersoluble complexes 51 and 52, [38] which were active catalysts for olefin-metathesis polymerization in water and methanol. Although these catalysts initiated ROMP of the endonorbornene 65 (see Scheme 18), the propagating species decomposed before polymerization was complete, and low conversions were observed.…”

Transition metal-based polymer chemistry: a critical micro-review

“…This requires the use of environmentally friendly alternatives. The most prominent ones are currently supercritical carbon dioxide [172 -177] as well as water itself [27,144,146,[178][179][180][181][182][183][184][185][186]. The latter is certainly not new in organic synthesis [187][188][189][190][191][192][193], yet still lacks comparable prominence in polymer chemistry.…”