vic‐Dichlorodiphosphapropenes – Synthesis and Coordination Ability

Abstract

New substituted 2,3‐dichloro‐1‐λ3σ2‐P,3‐λ3σ3‐P‐diphosphapropenes Mes*P=C(Cl)‐P(Cl)tBu (1) (Mes* = 2,4,6‐tri‐tert‐butylphenyl) and the oxidation compounds Mes*P=C(Cl)–P(=E)(Cl)R [R = tBu, E = S (2), O (3); R = Mes, E = O (4)] are reported. From the reaction of 2 with W(CO)5(thf) the chelate compound W(CO)4[Mes*P=C(Cl)–P(S)(Cl)tBu] (5) was obtained. Reaction of 1 or 2 with PdCl2(cod) led to PdCl2[cyMes*PC(H)(Cl)–P(Cl)tBu] (cyMes*P = 5,7‐di‐tert‐butyl‐3,3‐dimethyl‐1‐phosphaindane) (6) or PdCl2[cyMes*PC(H)(Cl)–P(S)(Cl)tBu] (7), in which the coordination to the Pd atoms is accompanied by intramolecular addition of CH(tBu) of Mes* to the P=C bond of the dichlorodiphosphapropene. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

New phosphorus containing bis-sulfone ligands

“…The formation of compound 3 was evidenced in solution by NMR spectroscopy, mainly through the 31 P NMR, where the presence of a singlet signal at a the chemical shift 201.6 ppm, downfield shifted compared to the dichlorophosphine 2, is characteristic for derivatives containing the -P=C< moiety. [3,8,[10][11][12]33] The 1 H and 13 C NMR spectra also confirm the formation of the expected compound 3, data are presented in experimental part. The dichlorophosphaalkene 3 is stable under inert atmosphere, and presents low stability at air, after a few days decomposition can be observed with the formation of the bis-sulfone ligand 1.…”

“…[10,13,22] The coupling constant of 615 Hz suggests the presence of a hydrogen atom linked to the phosphorus atom. [22] In the 1 H NMR spectrum of compound 4 slight downfield shifts can be observed for the signals for the methyl and tert-butyl group and the aromatic protons of the bis-sulfone ligand compared to the compound 2.…”

“…[ Since the stabilization of the first species containing low valent phosphorus atoms [7][8][9] the chemistry of these derivatives experienced a great development, becoming a versatile field of study. A large number of studies were reported over the years on the stability, reactivity and applications of P(III) containing derivatives, where the importance of these compounds was highlighted for their role as ligands in organometallic chemistry [1,3,10,16], in catalytic processes, [3] or compounds containing p-block elements. [5,6] The investigation of some derivatives containing phosphaalkenyl -P=C< moieties, their synthesis, characterisation and applications in organometallic and coordinative compounds, represents one of our research interests.…”

“…[5,6] The investigation of some derivatives containing phosphaalkenyl -P=C< moieties, their synthesis, characterisation and applications in organometallic and coordinative compounds, represents one of our research interests. [6,[10][11][12][13][14][15] In this study we investigated the connecting behaviour of the bissulfone 1,3-bis{(4-methylphenyl)sulfonyl}-5-tert-butylbenzene 1 as a ligand towards phosphorus tri-chloride PCl 3 in order to obtain new derivatives that can be used as building blocks in today's chemistry. The importance of bissulfone as ligands was recently highlighted as they function as pincer-type ligands for the stabilization of metallylenes and have an important effect in their reactivity.…”

Palladium and Ruthenium Derivatives Stabilised by bis-Sulfone Ligand

“…Among the large variety of ligands used for these complexes are for example different phosphines, [15] sulfoxides, [16] Schiff bases [17] or pincer ligands. [13,14,[18][19][20] Furthermore, the preparation of ligands with properties modulated by the presence of several functional groups like: metallylenes, [21][22][23] oxathia-derivatives, [24] germil-aminophosphoric esters, [25] phophaalkenyl derivatives [26][27][28] or organometallic halogenated derivatives [29][30][31] as well as their study for the stabilization of transition metals derivatives of palladium, ruthenium, gold, tungsten, etc., is a continuous concern in our team.…”