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 ...

Novel polyphosphines can be prepared by the base-catalysed addition of R, P-H across the carbon-carbon double bonds of vinylphosphonate esters, followed by reduction with lithium aluminium hydride. Thus a tertiary-primary diphosphine, a tertiary-diprimary triphosphine, a tertiary-triprimary tripod tetraphosphine, and a ditertiary-diprimary linear tetraphosphine have been prepared. Similarly, the tertiary-secondary diphosphine Ph,P*CH,-CH,*PH Ph can be prepared by base-catalysed addition of diphenylphosphine to isopropyl phenylvinylphosphinate followed by reduction. The secondary-primary diphosphine PhPH*CH,*CH,*PH, can be prepared by the Arbusov reaction of di-isopropoxy(pheny1)phosphine with di-isopropyl 2-bromoethylphosphonate followed by reduction. The i.r., l H n.m.r., sl P n.m.r.. and mass spectra of the new compounds are discussed.

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H and C6H5), and P(CH,CH,PH,), have been examined. Replacement of alkyls by hydrogen in R, P units consistently raises the 13C n.m.r. chemical shifts (i.e., lowers the 6 values) of CH, groups attached to this phosphorus. The spin-spin splittings in the 13C n.m.r. spectra by the phosphorus atoms in (C6H5)2PCH2CH,P(C6H5), and C6H5P[CH,CHzP-,], must be analysed as second-order ABX systems whereas those in the remaining polyphosphines can be analysed as first-order AMX systems. The range of significant phosphorus-carbon coupling in these compounds is limited to three bonds. In most cases, the coupling constants lJ(C-P) and 2J(C-P) have nearly equal magnitudes but opposite signs. However, direct bonding of hydrogen to a trivalent phosphorus atom appears to decrease markedly its 12J(C-P)I while having much less effect on its IIJ(C-P)I. This indicates that substitution on phosphorus of alkyls or aryls by hydrogens has a major effect on the conformation of the PCH,CH,P chain. 30602, U.S.A.RECENTLY Manii reported 13C n.m.r. chemical shifts and carbon-phosphorus coupling constants on an extensive series of tertiary phosphines. We were interested

Two isomers of the linear tetratertiary phosphine (C6H5)2ΡCH2CH2Ρ(C6H5)CH2H2Ρ(C6H5)CH2CH2Ρ- (C6H5)2 with widely differing solubilities and melting points can be obtained from the base-catalyzed addition of C6H5P(H)CH2CH2P(H)C6H5 to two equivalents of diphenylvinylphosphine; these appear to be the dl and meso diastereoisomers arising from the two equivalent asymmetric phosphorus atoms.