Poly(tertiary phosphines and arsines). X. Synthesis of methylated poly(tertiary phosphines)

Abstract

Novel methylated poly(tertiary phosphines) have been prepared mainly by the conversion of a P-H bond to a PCH2CH2P(CH& unit through base-catalyzed addition to CH2=CHP(S)(CH3)2 followed by desulfurization with LiAlH4 in boiling dioxane. Thus the di(tertiary phosphine) (C6H5)2PCH2CH2P(CH3)2 can be prepared from (C.#5)2PH and CHz=CHP(S)(CH&. The tri(tertiary phosphine) C6H5P[CH2CH2P(CH3)2]2 can be prepared similarly from CsHsPHz and CH2=CHP(S)(CH3)2. The tri(tertiary phosphine) CH3P[CH2CH2P(CsH5)2]2 can be prepared either from (CsH5)2PH and CH3P(S)(CH=CH2)2 or by the base-catalyzed addition of CH3PH2 to (C6H5)2PCH=CH2. The completely aliphatic tri(tertiary phosphine) CH3P[CH2CH2P(CH3)2]2 can be prepared either from CH3PH2 and CH2=CHP(S)(CH3)2 or from (CH3)zPH and CH3P(S)(CH=CH2)2. The linear tetra(tertiary phosphine) (CH3)2PCH2CH2P(C6H5)CH2CH2P(C6H5)CH2CH2P(CH3)2 can be prepared from C~H~P ( H ) C H~C H~P ( H ) C~H S and CH2=CHP(S)(CH&. The completely aliphatic tripod tetra(tertiary phosphine) P [ C H~C H~P ( C H~) Z ]~ can be prepared from (CH&PH and (CH2=CH)3PS or from (CH3)2PCH2CH2PH2 and CH2=CHP(S)(CH3)2. However, LiAIH4 reduction of the adduct P[CH2CH2P(S)(CH3)2]3 from PH3 and CHz=CHP(S)(CH3)2 in boiling dioxane results in hydrogenolysis rather than sample desulfurization to give the unusual di(tertiary)-secondary triphosphine HP[CH2CH2P(CH3)2]2. The penta(tertiary phosphine) [(CH3)2PCH2CH2]2PCH2CH2P(C6H5)CH2CH2P(CH3)2 can be prepared from C6H5P(H)CH2CH2PH2 and CH?=CHP(S)(CH3)2. The hexa(tertiary phosphine) [(CH3)2PCH2CH2]2PCH2-C H~P [ C H~C H~P ( C H~) Z ]~ can be prepared from (CH3)2PCH2CH2P(H)CH2CH2PH2 and CH2=CHP(S)(CH3)2. The proton and phosphorus-3 1 nmr spectra of these new poly(tertiary phosphines) are described.The first paper of this series4 describes the preparation of phenylated poly(tertiary phosphines) in which the phosphorus atoms are linked by -CH2CH2-bridges with the remaining positions on each phosphorus atom occupied by phenyl groups. Subsequent papers5-' describe extensive series of transition metal complexes formed by these phosphines.The phenylated poly(tertiary phosphines)s were ideal synthetic objectives to use for the development of reaction sequences for building up complex structures with PCH2CH2P units since the simpler ones are relatively airstable crystalline solids which can be handled and purified by conventional techniques. Detailed study of their metal complexes poses some major problems, however. Many of the metal complexes are only sparingly soluble and therefore difficult to study by nmr. Even in cases where proton nmr spectra can be obtained, neither the phenyl groups nor the CH2CH2 bridges give unequivocal structural information. The low solubility of some metal complexes prevents the use of column chromatography for their isolation and purification.Methylated poly(tertiary phosphines) offer several advantages over their phenylated analogs: more soluble metal complexes which are more readily purified and studied by nmr spectroscopy, a good proton nmr probe since each type ...

Oxidative addition capability of triphosphine iron and ruthenium complexes with methyl iodide

“…MeI was distilled over P 2 O 5 under a nitrogen atmosphere before use. MeP[CH 2 CH 2 PMe 2 ] 2 [6] and MeP[CH 2 CH 2 CH 2 PMe 2 ] 2 [7] were prepared according to reported procedures.…”

“…The tridentate phosphine ligands MeP(CH 2 CH 2 PMe 2 ) 2 [6] and MeP(CH 2 CH 2 CH 2 PMe 2 ) 2 [7] were prepared according to published procedures. The Journal of Organometallic Chemistry 689 (2004) 801-810 www.elsevier.com/locate/jorganchem ruthenium dicarbonyl complexes 1 and 2 have been obtained from the thermal reaction of Ru 3 (CO) 12 and the corresponding triphosphine ligand in refluxing toluene.…”

Nucleophilic and free-radical additions of phosphines and phosphine chalcogenides to alkenes and alkynes

“…Nucleophilic addition of phosphine to the double carbon-carbon bond in the presence of bases was first described by Rauhut et al 42,43 and later by King et al [44][45][46][47][48][49][50][51][52] for the alkenes with strong electron-withdrawing substituents. All these works are discussed in detail in a review.…”

“…[53][54][55][56][57][58][59][60][61] Thus, bis(2-arylethyl)-and bis(2-hetarylethyl)phosphines (1a-i) were selectively synthesized (Scheme 1) in 60-80% yield upon slow addition of alkene to a heated (45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60) o C)…”

Oligophosphan-Liganden, XXIV. Tris(2-dimethylphosphinophenyl)phosphan, P(C6H4PMe2-2)3 / Oligophosphine Ligands, XXIV. Tris(2-dimethylphosphinophenyl)phosphine, P(C6H4PMe2-2)3

“…Verlag der Zeitschrift für Naturforschung. D-7400 Tübingen 0 9 3 2 -0 7 7 6 /8 7 /0 9 0 0 -1110/$ 01.00/0 präparierende Tris(2-dimethylphosphinoethyl)phosphan, P(C H 2 C H 2 PM e2 ) 3 [7], sowie durch das zwar relativ leicht darzustellende, wegen seiner orthom etallierbaren Phenylsubstituenten für unsere Zwecke vermutlich aber wenig geeignete Tris(2-diphenylphosphinophenyl)phosphan, P(C6 H 4 PPh2-2) 3 [8 ], belegt. Die vorliegende A rbeit beschreibt daher Synthese, Charakterisierung und Eigenschaften der Titelverbindung.…”