cas 62336-24-7, 2-BROMOPHENYLDIPHENYLPHOSPHINE

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Coordination of a Diphosphine-Ketone Ligand to Ni(0), Ni(I), and Ni(II): Reduction-Induced Coordination
The coordination chemistry of the diphosphine-ketone ligand 2,2′-bis(diphenylphosphino)benzophenone (Phdpbp) with nickel is reported. The ketone moiety does not bind to Ni(II) in the complex (Phdpbp)NiCl2, whereas reduction to Ni(I) or Ni(0) induces η2(C,O) coordination of the ketone to form the pseudotetrahedral complexes (Phdpbp)NiCl and (Phdpbp)Ni(PPh3). DFT calculations indicate that the metal-ketone bond is dominated by π back-donation; hence, Phdpbp functions as a hemilabile acceptor ligand in this series of complexes. (Chemical Equation Presented).
Saes, Bartholomeus W. H.,Verhoeven, Dide G. A.,Lutz, Martin,Klein Gebbink, Robertus J. M.,Moret, Marc-Etienne
p. 2710 - 2713
(2015)
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Synthesis, characterization and luminescent properties of copper(I) halide complexes containing biphenyl bidentate phosphine ligand
Copper(I) halide complexes having thermally activated delayed fluorescence (TADF) and phosphorescence have attracted much attention. Here, a series of four-coordinate dinuclear copper(I) halide complexes, [CuX(bpbp)]2 (bpbp?=?2,2′-bis(diphenylphosphino)biphenyl, X?=?I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. The structural analysis reveals that two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four-membered Cu2X2 ring. These complexes exhibit yellow to blue emission in the solid state at room temperature and have peak emission wavelengths at 575–487?nm with microsecond lifetimes (τ?=?6.2–19.8?μs) and low emission quantum yields (0.01%). The emissions of 1–3 originate from MLCT, XLCT, and IL (intraligand) transitions. Three complexes displayed good thermal stability.
Chen, Bu-Lin,Liu, Li,Zhong, Xin-Xin,Asiri, Abdullah M.,Alamry, Khalid A.,Li, Guang-Hua,Li, Fa-Bao,Zhu, Nian-Yong,Wong, Wai-Yeung,Qin, Hai-Mei
p. 3907 - 3919
(2017)
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The structure of 2-(diphenylphosphino)phenyllithium: the significance of P-Li bonding
The solid state structure of 2-(diphenylphosphino)phenyllithiun*Et2O has been determined by a single crystal X-ray diffraction study.The crystal consists of dimeric aggregates in which the Li atoms are solvated by an additional diethyl ether molecule.The compound retains the dimeric structure in an apolar solvent (toluene) but in THF it exists in monomeric form.Ab initio calculations indicate a small but significant influence of P-Li interaction on the stability and structure of P-containing organolithium compounds.
Harder, Sjoerd,Brandsma, Lambert,Kanters, Jan A.,Duisenberg, Albert,Lenthe, Joop H. van
p. 143 - 154
(1991)
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Unilaterally Fluorinated Acenes: Synthesis and Solid-State Properties
The rapid development of organic electronics is closely related to the availability of molecular materials with specific electronic properties. Here, we introduce a novel synthetic route enabling a unilateral functionalization of acenes along their long side, which is demonstrated by the synthesis of 1,2,10,11,12,14-hexafluoropentacene (1) and the related 1,2,9,10,11-pentafluorotetracene (2). Quantum chemical DFT calculations in combination with optical and X-ray absorption spectroscopy data indicate that the single-molecule properties of 1 are a connecting link between the organic semiconductor model systems pentacene (PEN) and perfluoropentacene (PFP). In contrast, the crystal structure analysis reveals a different packing motif than for the parent molecules. This can be related to distinct F???H interactions identified in the corresponding Hirshfeld surface analysis and also affects solid-state properties such as the exciton binding energy and the sublimation enthalpy.
Bischof, Daniel,Breuer, Tobias,Grell, Yvonne,Hofmann, Philipp E.,Ivlev, Sergei I.,Koert, Ulrich,Schiller, Anna L. C.,Tripp, Matthias W.,Witte, Gregor
p. 16501 - 16505
(2020)
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ortho-Phosphoryl stabilized hypervalent iodosyl- and iodyl-benzene reagents
The synthesis and reactivity of a new IBX analogue (2-iodylphenyl)diphenyl- phosphine oxide 10 is described herein along with its analysis by single crystal X-ray diffraction.
Meprathu, Bindu V.,Justik, Michael W.,Protasiewicz, John D.
p. 5187 - 5190
(2005)
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The Trityl-Cation Mediated Phosphine Oxides Reduction
Reduction of phosphine oxides into the corresponding phosphines using PhSiH3 as a reducing agent and Ph3C+[B(C6F5)4]? as an initiator is described. The process is highly efficient, reducing a broad range of secondary and tertiary alkyl and arylphosphines, bearing various functional groups in generally good yields. The reaction is believed to proceed through the generation of a silyl cation, which reaction with the phosphine oxide provides a phosphonium salt, further reduced by the silane to afford the desired phosphine along with siloxanes. (Figure presented.).
Landais, Yannick,Laye, Claire,Lusseau, Jonathan,Robert, Frédéric
supporting information
p. 3035 - 3043
(2021/05/10)

Compound and application thereof
The compound has the structure shown in the formula (1), X is O or S, and L is selected from a single bond. A substituted or unsubstituted C5 - C60 arylene group, a substituted or unsubstituted C3 - C60 heteroarylene group, the Ar being selected from one of a substituted or unsubstituted C5 - C60 aryl group, a substituted or unsubstituted C3 - C60 heteroaryl group, and the - L-Ar is not selected from phenyl, biphenyl, or cyano substituted phenyl. When the compound provided by the invention is applied OLED devices, the efficiency of the device can be effectively improved, the driving voltage is reduced, and the compound is a good-performance electronic transmission material.
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Paragraph 0102-0106; 0123-0127

(2021/09/21)

Mixed Alkyl/Aryl Diphos Ligands for Iron-Catalyzed Negishi and Kumada Cross Coupling Towards the Synthesis of Diarylmethane
Mixed alkyl/aryl diphos ligands have been prepared and their application in iron-catalyzed cross coupling of benzylic chlorides with diaryl zinc (Negishi) or aryl Grignard reagents (Kumada) towards the synthesis of diarylmethane has been evaluated. The iron?diphos catalytic system exhibited the enhanced activity and selectivity in the two coupling reactions. The electron-rich mixed PPh2/PCy2 ligands outperformed their symmetrical PPh2 congeners, and led to decreased homocoupling byproduct formation. It indicates that the electronic effect of the ligands plays an important role in the catalytic performance. The Fe catalyst supported by L8 bearing an electron-rich PCy2 substituent and a sterically demanding tert-butyl on ethene backbone exhibited the best catalytic performance and good functional group tolerance in the two cross coupling reactions.
Ma, Xufeng,Wang, Han,Liu, Yao,Zhao, Xing,Zhang, Jun
p. 5134 - 5140
(2021/11/16)

Ru catalyzed hydrogenation of CO2 to formate under basic and acidic conditions
The hydrogenation of CO2 to MeOH is pertinent to advance future energy schemes. Towards this end, phosophine-ligated Ru catalysts have been shown to achieve this transformation under either acidic or basic conditions. In this manuscript, we screen catalytic conditions for a novel tris(phosphine) ligand with Ru to see if it can facilitate the conversion of CO2 to MeOH under both acidic and basic conditions. With both sets of conditions, we observe hydrogenation of CO2 to formate. This work shows that the same catalytic system can function under both reaction types but is limited to formate production.
Cannon, Austin T.,Saouma, Caroline T.
(2021/08/03)

C-F activation for C(sp2)-C(sp3) cross-coupling by a secondary phosphine oxide (SPO)-nickel complex
A secondary phosphine oxide (SPO)-nickel catalyst allowed the activation of otherwise inert C-F bonds of unactivated arenes in terms of challenging couplings with primary and secondary alkyl Grignard reagents. The C-F activation is characterized by mild reaction conditions and high levels of branched selectivity. Electron-rich and electron-deficient arenes were suitable electrophiles for this transformation. In addition, this strategy also proved suitable to heterocycles and for the activation of C-O bonds under slightly modified conditions.
Müller, Valentin,Ghorai, Debasish,Capdevila, Lorena,Messinis, Antonis M.,Ribas, Xavi,Ackermann, Lutz
supporting information
p. 7034 - 7040
(2020/09/15)

Organic long afterglow material containing triphenylphosphine (triphenylphosphine oxide) and preparation method and use method thereof
The invention relates to an organic long afterglow material containing triphenylphosphine (triphenylphosphine oxide). The molecular structure of the organic long afterglow material is TP(O)-R, whereinTP(O) is a triphenylphosphine (triphenylphosphine oxide) group; R is an aromatic ring or an aromatic heterocyclic compound; TP(O) and R groups are connected in an ortho-position mode, the synthesizedluminescent material has a spiral molecular configuration, non-radiative transition is effectively inhibited under the large steric hindrance configuration and strong intramolecular action, long afterglow luminescence is achieved, and the luminescence wavelength, phosphorescence lifetime and other properties of a final product can be adjusted by introducing different functional groups. The synthesis method disclosed by the invention is simple in process and easy to purify, the synthesized luminescent material has the spiral molecular configuration, the non-radiative transition is effectivelyinhibited under the large steric hindrance configuration and strong intramolecular action, the long afterglow luminescence is realized, and the luminescence wavelength, phosphorescence lifetime and other properties of the final product can be adjusted by introducing different functional groups. The organic long afterglow material is applied to the fields of organic photoelectricity, biological imaging, counterfeiting prevention and the like.
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Paragraph 0030; 0034-0036; 0041-0044

(2020/11/26)

M-CAr-H Bond Alkylations and Difluoromethylation of Tertiary Phosphines Using a Ruthenium Catalyst
m-CAr-H bond functionalization of tertiary phosphines was developed using [Ru(p-cymene)Cl2]2 as a catalyst. Desired product structures were confirmed by single-crystal X-ray diffraction. Mechanistic experiments indicated that m-CAr-H bond functionalization was a radical reaction and that a hexagonal ruthenacycle complex was a crucial intermediate in the process. Therefore, this study provides a novel method for the late-stage meta-position modification of biphenyl monophosphine ligands.
An, Jiangzhen,Jia, Chunqi,Li, Gang,Wang, Junjie,Yan, Bingxu,Yang, Suling,Zhong, Lei
supporting information
p. 9450 - 9455
(2020/12/22)

EUROPIUM COMPLEX
To provide europium complexes having high photostability. A europium complex expressed with the following formula (A): {wherein, RA and RB are independently a cyclic alkyl group with 3 to 10 carbons, respectively, and RC is a cyclic alkyl group with 3 to 10 carbons or a phenyl group expressed with the following formula (B): (wherein, XA, XB, AC, XD and XE independently represent a hydrogen atom; a fluorine atom; an alkyl group with 1 to 3 carbon(s); an alkyloxy group with 1 to 3 carbon(s); an aryloxy group with 6 to 10 carbons; a fluoroalkyl group with 1 to 3 carbon(s); a fluoroalkyloxy group with 1 to 3 carbon(s); or a phenyl group that may be substituted with a fluorine atom, an alkyl group with 1 to 3 carbon(s), an alkyloxy group with 1 to 3 carbon(s), a fluoroalkyl group with 1 to 3 carbon(s), a fluoroalkyloxy group with 1 to 3 carbon(s), a fluorophenyl group, a hydroxyl group or a cyano group, respectively); RA is a cyclic alkyl group with 3 to 10 carbons; RB and RC are a phenyl group expressed with the formula (B), provided, however, that a case where RA a cyclohexyl group, and, RB and RC are a phenyl group is excluded; or RA, RB and RC independently represent an ortho-substituted phenyl group expressed with the following formula (Ba): (wherein, XE represents a hydrogen atom, an alkyl group with 1 to 3 carbon(s), an alkyloxy group with 1 to 3 carbon(s), a fluoroalkyl group with 1 to 3 carbon(s), a fluoroalkyloxy group with 1 to 3 carbon(s), a naphthyl group that may be substituted with a fluorine atom, a pyridyl group that may be substituted with a fluorine atom, or a phenyl group that is expressed with a formula (C): [wherein, ZA, ZC and ZE independently represent a hydrogen atom, a fluorine atom, an alkyl group with 1 to 3 carbon(s), an alkyloxy group with 1 to 3 carbon(s), a fluoroalkyl group with 1 to 3 carbon(s), a fluoroalkyloxy group with 1 to 3 carbon(s), a phenyl group that may be substituted with a fluorine atom, a hydroxyl group or a cyano group; ZB and ZD independently represent a hydrogen atom or a fluorine atom, respectively], provided, however, that a case where RA, RB and RC are all a phenyl group is excluded), respectively; RD represents a hydrogen atom, a deuterium atom or a fluorine atom; WA and WB independently represent an alkyl group with 1 to 6 carbon(s), a fluoroalkyl group with 1 to 6 carbon(s), a phenyl group, a 2-thienyl group or a 3-thienyl group; and ‘n’ represents an integer of 1 to 3}.
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Paragraph 0362-0364

(2020/11/23)

Catalytic Systems for Production of 1-Hexene by Selective Ethylene Trimerization
Abstract: New chromium complexes with diphosphine ligands have been obtained by the reaction of chromium(III) hexahydrate and diphosphines in acetone. The structure of chromium(III) complex 4 containing water molecule and 1,2-bis(diphenylphosphino)benzene as ligands and that of two chromium(III) complexes (12 and 13) with 1,2-bis(diphenylphosphino)benzene ligands containing alkenyl substituents in the ortho-position of one of the phenyl groups at the phosphorous atom have been determined using X-ray diffraction analysis. The catalytic properties of the obtained complexes in the composition of catalytic systems for ethylene trimerization have been studied. It has been shown that the obtained series of catalytic systems manifests high activity in the process of ethylene trimerization to 1-hexene, with the process selectivity exceeding 94%. The highest value of productivity amongst known selective catalytic systems for trimerization was achieved using a chromium complex 13 bearing the 2-methylprop-1-enyl group at the ortho-position of one of the phenyl groups. The influence of temperature, pressure, the nature of the solvent and the composition of the catalytic system on the parameters of the process of ethylene trimerization to form 1-hexene has been determined.
Afanas’ev, V. V.,Bespalova, N. B.,Cheredilin, D. N.,Kozlova, G. A.,Senin, A. A.,Sheloumov, A. M.
p. 55 - 68
(2020/02/25)

Ruthenium-Catalyzed Gram-Scale Preferential C-H Arylation of Tertiary Phosphine
A general protocol for site-preferential mono-C-H arylation of tertiary phosphine ligands catalyzed by a ruthenium(II) complex was devised. This protocol gives access to a series of modified Buchwald-biaryl monophosphines on a gram scale in moderate to excellent yields. A catalytic cycle is proposed derived from knowledge of the intermediates observed by ESI-MS. Importantly, these monoarylated products could be further transformed into dibenzophosphole derivatives.
Li, Jia-Wei,Wang, Liang-Neng,Li, Ming,Tang, Pan-Ting,Luo, Xiao-Peng,Kurmoo, Mohamedally,Liu, Yue-Jin,Zeng, Ming-Hua
supporting information
p. 2885 - 2889
(2019/04/30)

Catalytic Properties of Chromium Complexes Based on 1,2-Bis(diphenylphosphino)benzene in the Ethylene Oligomerization Reaction
Abstract: The activity of the catalyst systems of a number of diphosphine ligands and chromium complexes based on 1,2-bis(diphenylphosphino)benzene in the ethylene oligomerization reaction has been studied. Structural modifications of diphosphine ligands have been performed to create selective catalyst systems for ethylene oligomerization. It has been shown that the introduction of ortho-functional groups into one of the phenyl substituents at the phosphorus atom in diphosphine ligands makes it possible to carry out the process of ethylene oligomerization to 1-hexene with the selectivity of 90 wt % and above. One of the complexes (chromium complex 15) with a functionalized diphosphine ligand has been characterized by X-ray structure analysis. The influence of the change in the amount of the activator and its type on the activity of the catalyst systems has been studied. It has been shown that the replacement of some organoaluminum activator, methylaluminoxane, by trimethylaluminum does not decrease the productivity and selectivity of the catalyst systems based on diphosphine chromium complexes.
Cheredilin,Sheloumov,Senin,Kozlova,Afanas’ev,Bespalova
p. S72 - S87
(2020/01/23)

Stabilized Carbenium Ions as Latent, Z-type Ligands
Controlling the reactivity of transition metals using secondary, σ-accepting ligands is an active area of investigation that is impacting molecular catalysis. Herein we describe the phosphine gold complexes [(o-Ph2P(C6H4)Acr)AuCl]+ ([3]+; Acr=9-N-methylacridinium) and [(o-Ph2P(C6H4)Xan)AuCl]+ ([4]+; Xan=9-xanthylium) where the electrophilic carbenium moiety is juxtaposed with the metal atom. While only weak interactions occur between the gold atom and the carbenium moiety of these complexes, the more Lewis acidic complex [4]+ readily reacts with chloride to afford a trivalent phosphine gold dichloride derivative (7) in which the metal atom is covalently bound to the former carbocationic center. This anion-induced AuI/AuIII oxidation is accompanied by a conversion of the Lewis acidic carbocationic center in [4]+ into an X-type ligand in 7. We conclude that the carbenium moiety of this complex acts as a latent Z-type ligand poised to increase the Lewis acidity of the gold center, a notion supported by the carbophilic reactivity of these complexes.
Wilkins, Lewis C.,Kim, Youngmin,Litle, Elishua D.,Gabba?, Fran?ois P.
supporting information
p. 18266 - 18270
(2019/11/14)

Development of a novel secondary phosphine oxide-ruthenium(II) catalyst and its application for carbonyl reduction
A secondary phosphine oxide-phosphine mixed tridentate ligand and its ruthenium complex have been developed. This complex shows excellent catalytic activity for carbonyl reduction, especially for the reduction of α,β-unsaturated aldehydes. The turnover number and selectivity can reach up to 36500 and 99%, respectively. Control experiments and DFT calculations supported an outer-sphere mechanism during the hydrogenation reaction.
Tan, Xuefeng,Zeng, Weijun,Zhang, Xiaoyong,Chung, Lung Wa,Zhang, Xumu
supporting information
p. 535 - 538
(2018/01/19)

Tridentate phosphine ligand, catalyst and preparation method and application thereof
The invention belongs to the field of asymmetric catalysis, and discloses tridentate phosphine ligand which is of a structure of formula I as shown in the specification, wherein R is aryl or substituted aryl. The invention further discloses a catalyst prepared from the ligand. The catalyst is of a structure of formula II as shown in the specification, wherein R is aryl or substituted aryl, and L is mono-phosphine ligand. The invention further discloses application of the catalyst in a catalytic reduction reaction. The invention provides a tridentate phosphine ligand which is novel in structure, and a ruthenium complex of the tridentate phosphine ligand. carbonyl compounds, namely aldehyde and ketone, particularly alpha,beta-unsaturated aldehyde, are reduced by using the ruthenium complex, and very good reaction activity and selectivity are achieved.
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Paragraph 0026; 0028; 0029

(2017/12/30)

Allosteric Effects in Ethylene Polymerization Catalysis. Enhancement of Performance of Phosphine-Phosphinate and Phosphine-Phosphonate Palladium Alkyl Catalysts by Remote Binding of B(C6F5)3
Remote binding of B(C6F5)3 to (PPO)PdMeL (L = pyridine or lutidine) or {(PPO)PdMe}2 ethylene polymerization catalysts that contain phosphine-arenephosphinate or phosphine-arenephosphonate ligands (PPO- = [1-PAr2-2-PR′O2-Ph]-: Ar = R′ = Ph (1a); Ar = Ph, R′ = OEt (1b); Ar = Ph, R′ = OiPr (1c); Ar = 2-OMe-Ph, R′ = OiPr (1d)) significantly increases the catalyst activity and the molecular weight of the polyethylene (PE) product. In the most favorable case, in situ conversion of (1d)PdMe(py) to the base-free adduct {1d·B(C6F5)3}PdMe increases the ethylene polymerization activity from 9.8 to 5700 kg mol-1 h-1 and the Mn of the PE product from 9030 to 99 200 Da (80 °C, 410 psi). X-ray structural data, trends in ligand lability, and comparative studies of BF3 activation suggest that these allosteric effects are primarily electronic in origin. The B(C6F5)3 binding enhances the chain growth rate (Rgrowth) by increasing the degree of positive charge on the Pd center. This effect does not result in the large increase in the chain transfer rate (Rtransfer) and concomitant reduction in PE molecular weight seen in previous studies of analogous (PO)PdRL catalysts that contain phosphine-arenesulfonate ligands, because of the operation of a dissociative chain transfer process, which is inhibited by the increased charge at Pd.
Wilders, Alison M.,Contrella, Nathan D.,Sampson, Jessica R.,Zheng, Mingfang,Jordan, Richard F.
supporting information
p. 4990 - 5002
(2018/02/07)

Designing P-Chirogenic 1,2-Diphosphinobenzenes at Both P-Centers Using P(III)-Phosphinites
A new enantiodivergent synthesis of P-chirogenic 1,2-diphosphinobenzenes (DP?B) bearing the chirality on one or both phosphorus centers is reported using aryne chemistry. The principle is based on successive reactions of 1,2-dibromobenzene with sec-phosphide boranes, then DABCO to remove the borane, and finally with chlorophosphines or P(III)-chirogenic phosphinites. The efficiency of this synthesis was demonstrated by the stereoselective preparation of (S,S)-1,2-bis(o-anisylphenylphosphino)benzene. A comparison of DIPAMP and homochiral DP?B ligands in asymmetric Rh- or Pd-catalyzed reactions was reported.
Bayardon, Jér?me,Rousselin, Yoann,Jugé, Sylvain
p. 2930 - 2933
(2016/07/06)

Effect of silylated triarylphosphine ligands on rhodium-catalyzed hydrosilylation
A series of silylated triarylphosphines was synthesized. Hydrosilylation reactions of styrene with triethoxysilane catalyzed by RhCl3/silylated triarylphosphine complexes were investigated. The complexes RhCl3/phenylbis(4-trimethylsilylphenyl)phosphine and RhCl3/tris(4-trimethylsilylphenyl)phosphine exhibited higher activity as well as greater β-adduct selectivity, and no unsaturated product was obtained. The results suggest that the silyl moieties have a significant impact on the catalytic process. Copyright
Li, Jiayun,Xue, Mei,Bai, Ying,Peng, Jiajian,Xiao, Wenjun
p. 905 - 910
(2016/10/18)

A composite material containing organic and inorganic organophosphine organophosphine compd. and use thereof
PROBLEM TO BE SOLVED: To provide a phosphine compound utilizable as a silane coupling agent usable as a precursor for forming a covalent bond with an inorganic oxide by introducing a silyl group having a leaving substituent to the phosphine compound.SOLUTION: The phosphine compound is represented by formula (1), wherein Rand Rare each independently an aryl group or an alkyl group; Y is an aryl group or an alkyl group; X, when Y is an aryl group, is one group selected from the group consisting of a halogen atom, an alkoxy group, a hydroxy group and an amino group, and when Y is an alkyl group, is one group selected from the group consisting of an alkoxy group, a hydroxy group and an amino group; and n is an integer of 1 to 3.
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Paragraph 0018

(2017/02/02)

Effect of triarylphosphane ligands on the rhodium-catalyzed hydrosilylation of alkene
A series of triarylphosphanes (1a, 2a, 3a, 4a, 5a, 6a, 7a, 8a, 9a, 10a, 11a) have been synthesized. An X-ray crystal structure analysis of (2-bromophenyl)diphenylphosphane (1a) unambiguously confirmed the constitution of the functionalized phosphane. The hydrosilylation reaction of styrene with triethoxysilane catalyzed with RhCl3/triarylphosphane was studied. In comparison with the classic Wilkinson's catalyst, rhodium complexes with functionalized triarylphosphane ligands are characterized by a very high catalytic effectiveness for the hydrosilylation of alkene. Among these catalysts tested, RhCl3/diphenyl(2-(trimethylsilyl)phenyl)phosphane (8a) exhibited excellent catalytic properties. Using this silicon-containing phosphane ligand for the rhodium-catalyzed hydrosilylation of styrene, both higher conversion of alkene and higher β-adduct selectivity were obtained than with Wilkinson's catalyst.
Xue, Mei,Li, Jiayun,Peng, Jiajian,Bai, Ying,Zhang, Guodong,Xiao, Wenjun,Lai, Guoqiao
p. 120 - 126
(2014/02/14)

Tailoring buchwald-type phosphines with pyrimidinium betaines as versatile aryl group surrogates
A derivatization of dialkylbiarylphosphines consisting in the formal replacement of their distal aryl group by a pyrimidinium betaine is reported. Two achiral representatives of this new class of Buchwald-type phosphines have been successfully synthesized through two strategies. The first one is based on a last stage introduction of the phosphino moiety, and the second one consists in a modular, one-pot, three-step procedure starting from an o-bromoaryl phosphine. The resulting phosphines have been coordinated onto gold(I) and palladium(II) centers and have been employed as supporting ligands in Pd-catalyzed Suzuki-Miyaura cross-coupling of aryl halide substrates.
Nol-Duchesneau, Ludovik,Lugan, Nol,Lavigne, Guy,Labande, Agns,Csar, Vincent
supporting information
p. 5085 - 5088
(2014/12/11)

P-CHIROGENIC ORGANOPHOSPHORUS COMPOUNDS
The present invention relates to novel P-chirogenic organophosphorus compounds of general formula (I). The present invention also provides a process for the synthesis of said compounds of formula (I). The present invention also relates to intermediate products of general formulae (II), (III) and (IV), as shown below, which are involved in the synthesis of compounds (I). Further, the invention relates to metal complexes comprising compounds (I) as ligands. The novel compounds and complexes of the present invention are useful in asymmetric catalysis by transition metal complexes or organocatalysis, especially for asymmetric hydrogenation or allylation. Compounds of general formula (I) may useful as agrochemical and therapeutic substances, or as reagents or intermediates for fine chemistry.
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Page/Page column 47; 48

(2013/03/26)

Phosphorescent Ir(iii) complexes with both cyclometalate chromophores and phosphine-silanolate ancillary: Concurrent conversion of organosilane to silanolate
Ir(iii) metal complexes with general formula [(C^N)2Ir(P^SiO)], where (C^N)H is 2-phenylisoquinoline (1), 2-phenylpyridine (2) or 2-(2,4-difluorophenyl)pyridine (3), and (P^SiO)H is an organosilanolate ancillary chelate with either diphenylsilyl (a) or dimethylsilyl (b) substituent, were synthesized, among which the structure of 3a was also confirmed using single-crystal X-ray diffraction analyses. These complexes exhibit bright phosphorescence in the region of 489-632 nm in solution at room temperature, showing the first successful example of using organosilanolate as an ancillary chelate. For application, organic light emitting diodes (OLEDs) using phosphors 3a and 3b doped in N,N′-dicarbazolyl-3,5-benzene (mCP) exhibited a maximum brightness of 50 800 cd m-2 at 800 mA cm -2 (12 V) with ηext of 10.1% and a brightness of 45 900 cd m-2 at 700 mA cm-2 (14.5 V) with ηext of 10.2%, respectively. The Royal Society of Chemistry 2013.
Zhang, Fushi,Wang, Liduo,Chang, Shih-Han,Huang, Kuan-Lin,Chi, Yun,Hung, Wen-Yi,Chen, Chih-Ming,Lee, Gene-Hsiang,Chou, Pi-Tai
p. 7111 - 7119
(2013/08/25)

Stereoselective synthesis of o-bromo (or iodo)aryl P-chirogenic phosphines based on aryne chemistry
The efficient synthesis of chiral or achiral tertiary phosphines bearing an o-bromo (or iodo)aryl substituent is described. The key step of this synthesis is based on the reaction of a secondary phosphine borane with the 1,2-dibromo (or diiodo)arene, owing to the formation in situ of an aryne species in the presence of n-butyllithium. When P-chirogenic secondary phosphine boranes were used, the corresponding o-halogeno-arylphosphine boranes were obtained without racemization in moderate to good yields and with ee up to 99%. The stereochemistry of the reaction, with complete retention of the configuration at the P atom, has been established by X-ray structures of P-chirogenic o-halogenophenyl phosphine borane complexes. The decomplexation of the borane was easily achieved without racemization using DABCO to obtain the free o-halogeno-arylphosphines in high yields.
Bayardon, Jerome,Laureano, Hugo,Diemer, Vincent,Dutartre, Mathieu,Das, Utpal,Rousselin, Yoann,Henry, Jean-Christophe,Colobert, Francoise,Leroux, Frederic R.,Juge, Sylvain
p. 5759 - 5769
(2012/08/08)

Lewis acids and lewis acid-functionalized ligands in rhodium-catalyzed methyl acetate carbonylation
The application of Lewis acids and Lewis acid-functionalized ligands as activators for methyl acetate in the rhodium-catalyzed carbonylation of methyl acetate to acetic anhydride has been investigated. The reaction of methyl acetate with B(C6F5)3 results in the formation of the adduct [MeOAc·B(C6F5)3]. The combination of this adduct with [Rh(OAc)(CO)2]2 results in a transfer of the Lewis acid to the rhodium complex, rather than an anticipated oxidative addition reaction. In a second approach, novel Lewis acid-functionalized rhodium(I) complexes [Rh(CO)Cl(BPP)], [Rh(CO) 2(BPP)]SbF6, and [Rh(MeCN)2(BPP)]SbF 6 (BPP = PhB(C6H4PPh2)2) have been prepared. The lack of reactivity of [Rh(CO)2(BPP)]SbF 6 toward MeOAc has shown that the rhodium-boron interaction is too strong for activation of methyl acetate, and no carbonylation activity was observed under the conditions used.
Conifer, Christopher M.,Law, David J.,Sunley, Glenn J.,White, Andrew J. P.,Britovsek, George J. P.
experimental part
p. 4060 - 4066
(2011/10/03)

Novel phosphite palladium complexes and their application in C-P cross-coupling reactions
A mono- and a 1,3-bis-phosphite arene ligand based on 2,2′-biphenol have been synthesized in order to study the synthesis of the corresponding palladium(II) complexes starting from different Pd precursors. Novel bis-phosphite palladium complex 1 [PdCl2(L)2] (L = dibenzo[d,f][1,3,2]dioxaphosphepin, 6-phenoxy), C,P-chelate bonded monophosphite palladium complex 2 [Pd(κ2-L)(μ-Cl)]2, and PCP-pincer palladium complex 3 have been prepared from these ligands in promising to excellent yields (50-95%). Additionally, complexes 1 and 3 have been characterized by X-ray crystal structure determinations. The application of 2,6-bis-phosphite pincer palladium(II) complex 3 in C-P cross-coupling between diphenylphosphine-borane and a wide range of various aryl iodides under very mild conditions is reported. Kinetic investigations indicate that 3 merely acts as a pre-catalyst and that Pd nanoparticles are the actual catalytically active species.
Li, Jie,Lutz, Martin,Spek, Anthony L.,Van Klink, Gerard P.M.,Van Koten, Gerard,Klein Gebbink, Robertus J.M.
experimental part
p. 2618 - 2628
(2010/11/21)

Chiral mixed secondary phosphine-oxide-phosphines: High-performing and easily accessible ligands for asymmetric hydrogenation
P&O: Combining secondary phosphine oxides (SPOs) with phosphines leads to highly effective chiral bidentate ligands for transition-metal-based catalysts. JoSPOphos and TerSPOphos are readily accessible from inexpensive starting materials. The steric and electronic properties of these modular ligands can be easily tuned. In the asymmetric hydrogenation of functionalized alkenes, their rhodium complexes reacted to give enantioselectivities of up to 99% ee and turnover frequencies of up to 20000 h-1 Chemical equation Presented
Landert, Heidi,Spindler, Felix,Wyss, Adrian,Blaser, Hans-Ulrich,Pugin, Benoit,Ribourduoille, Yann,Gschwend, Bjoern,Ramalingam, Balamurugan,Pfaltz, Andreas
experimental part
p. 6873 - 6876
(2010/12/19)

DIPHOSPHINE LIGANDS
Compounds of the formulae I and Ia in the form of mixtures of diastereomers or pure diastereomers, (I), (Ia), where R1 is a hydrogen atom or C1-C4-alkyl and R'1 is C1-C4-alkyl; X1 and X2 are each, independently of one another, a sec-phosphino group; T is C6-C20-arylene or C4-C18- heteroarylene having heteroatoms selected from the group consisting of O, S, -N= and N(C1-C4-alkyl); v is 0 or an integer from 1 to 4; X1 is bound in the ortho position relative to the T-C* bond; Q is vinyl, methyl, ethyl, -CH2-OR, -CH2-N(C1-C4-alkyl)2 or a C- or S-bonded chiral group which directs metals of metallation reagents into the ortho position; R is hydrogen, a silyl radical or an aliphatic, cycloaliphatic, aromatic or aromatic-aliphatic hydrocarbon radical which has from 1 to 18 carbon atoms and is unsubstituted or substituted by C1-C4-alkyl, C1-C4-alkoxy, F or CF3; are ligands for metal complexes as homogeneous catalyst in asymmetric syntheses.
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Page/Page column 27

(2008/06/13)

Probing the importance of the hemilabile site of bis(phosphine) monoxide ligands in the copper-catalyzed addition of diethylzinc to N-phosphinoylimines: Discovery of new effective chiral ligands
(Chemical Equation Presented) The hemilabile ligand Me-DuPHOS(O) 2 has proven to be a successful ligand for the copper-catalyzed addition of diethylzinc to N-phosphinoylimines. The corresponding α-chiral amines were obtained in high yields (80-98%) and enantiomeric ratios (19.0:1 to 99.0:1 er). Furthermore, this Cu?2 catalytic system has been shown to be effective in the addition of diethylzinc to nitroalkenes and in the reduction of β,β-disubstituted vinyl phenyl sulfones. This paper describes a general structure/selectivity study in which the three ligand subunits (chiral phospholane-linker-labile coordinating group (Z)) are systematically modified and tested in the copper-catalyzed addition of diethylzinc to the N-phosphinoylimine 1 derived from benzaldehyde. This study led to the discovery of a new class of effective chiral ligands that combine a chiral phospholane unit and an achiral phosphine oxide.
Bonnaventure, Isabelle,Charette, Andre B.
p. 6330 - 6340
(2008/12/22)

Superior effect of a π-acceptor ligand (phosphine-electron-deficient olefin ligand) in the Negishi coupling involving alkylzinc reagents
(Chemical Equation Presented) Palladium-catalyzed Negishi cross-coupling involving primary and secondary alkyls, even in the presence of β-H, can be achieved at ambient temperature using chelating ligands containing a phosphine and an electron-deficient olefin. The superior effects of the ligands were shown not only in the desired cross-coupling product yields but also in the fast reaction at mild conditions. This reaction has been also scaled up to 50 g in 0.005 mol % catalyst (20,000 TONs) at room temperature.
Luo, Xiancai,Zhang, Heng,Duan, Hui,Liu, Qiang,Zhu, Lizheng,Zhang, Tony,Lei, Aiwen
p. 4571 - 4574
(2008/03/12)

Modular multidentate phosphine ligands: Application to palladium-catalyzed allylic alkylations
Multidentate phosphines were readily obtained by reaction of chiral multidentate amines, prepared via ring opening of (S)-N-tosyl-2- isopropylaziridine with ammonia, primary, and secondary amines, with achiral phosphorus containing building blocks. The phosphines were used in palladium-catalyzed alkylation of rac-3-cyclohexenyl and cyclopentenyl carbonates. The enantioselectivity and reactivity were largely dependent on the structure of the amine core of the ligands. Up to 88% ee was observed in reactions with the six-membered substrate. The Royal Society of Chemistry 2006.
Pei, Yuxin,Brule, Emilie,Moberg, Christina
p. 544 - 550
(2008/02/02)

Complexes of iron and cobalt with new tripodal amido-polyphosphine hybrid ligands
Divalent complexes of iron and cobalt with new, monoanionic tripodal amido-polyphosphine ligands have been thoroughly characterized, and XRD analysis reveals geometries that are distinct for this class of ligand. The Royal Society of Chemistry 2006.
Whited, Matthew T.,Rivard, Eric,Peters, Jonas C.
p. 1613 - 1615
(2008/02/08)

Palladium-catalysed synthesis of biaryl phosphines
Monodentate, biphenyl-type phosphines have emerged as a powerful class of ligands in homogeneous catalysis. Synthetic methods for these ligands are limited, however. We report that the palladium-catalysed Suzuki coupling of OPR2(o-C6H4X) (R=Ph, t-Bu; X=Br, I) with arylboronic acids affords a variety of biaryl phosphine oxides including those that contain heterocycles. The corresponding phosphines are readily obtained by treatment with HSiCl3. The methodology provides an easy entry to monodentate biaryl and heterobiaryl Poverlapping logical AND signX (X=N, O, S) phosphines with diverse steric and electronic properties.
Baillie, Colin,Xiao, Jianliang
p. 4159 - 4168
(2007/10/03)

Practical synthesis of chlorosilyl-functionalized triphenylphosphanes
A practical synthesis of ortho-dialkylchlorosilyl-functionalized triarylphosphanes has been developed. An X-ray crystal structure analysis of phosphane 3 unambiguously confirmed the constitution of the new phosphane functionalized chlorosilanes. It also showed an interesting P/Si interaction, which may render this compound a model for the early stages of the mechanism of SN2 nucleophilic displacement at silicon.
Quintard, Delphine,Keller, Manfred,Breit, Bernhard
p. 905 - 908
(2007/10/03)

Copper-catalyzed C-P bond construction via direct coupling of secondary phosphines and phosphites with aryl and vinyl halides
(Matrix presented) A general method for the coupling of aryl and vinyl halides with diaryl and dialkyl phosphines, as well as with dibutyl phosphite, is reported. This highly efficient transformation is realized through the use of copper(I) iodide as a catalyst, N,N′-dimethylethylenediamine as a ligand, and Cs2CO3 as a base. A variety of sterically hindered and/or functionalized substrates were found to react under these reaction conditions to provide products in good to excellent yields.
Gelman, Dmitri,Jiang, Lei,Buchwald, Stephen L.
p. 2315 - 2318
(2007/10/03)

Process for producing optically active amide from alpha beta- unsaturated amide derivative in the presence of transition metal complex containing phosphine-phosphorane compound and transition metal
A novel process for producing an optically active amide excellent in chemical selectivity and enantioselectivity by asymmetric hydrogenation of an α,β-unsaturated amide and also allowing the reaction to proceed efficiently even when a trace amount of a catalyst is used relative to the substrate as compared with the amount in a conventional process. An optically active amide is produced by asymmetric hydrogenation of an α,β-unsaturated amide derivative in the presence of a transition metal complex containing a specific phosphine-phosphorane compound.
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(2008/06/13)

Water soluble phosphines Part XV. Syntheses of multiply functionalized and chiral phospine ligands by Pd-catalyzed P-C and C-C coupling reactions
Phosphine ligands containing mono- and multiply substituted aromatic substituents (1-13, 19a and 19b) are accessible in high yields by palladium-catalyzed P-C coupling reactions between primary, secondary or disecondary phosphines and iodo- or bromoaromatic compounds. The reaction is of broad applicability and compatible with electron donor or electron acceptor substituents in ortho, meta or para position to the halogen in the aromatic ring systems. It may be performed in protic and aprotic solvents. The chiral spirocyclic boronato complex 15a is formed upon reaction of 3 with boric acid, while with benzeneboronic acid 15c with a peripheral Lewis acid group is obtained. The Pd-mediated P-C coupling reaction of primary phosphines proceeds stepwise, tailor-made chiral secondary (16) and tertiary phosphines (17) being formed in high yield. Through combination with Suzuki-type C-C coupling reactions, the scope of Pd-catalyzed P-C coupling may be extended further, novel ligands (20a, 20b, 21a, 21b) with biphenylyl substituents being accessible. The X-ray structures of the salicylic acid derivative 3 (space group P1) and of ortho-iso-propylphenyl-diphenylphosphine 6 (space group Pbca) have been determined.
Brauer, David J.,Hingst, Martin,Kottsieper, Konstantin W.,Liek, Christian,Nickel, Thomas,Tepper, Michael,Stelzer, Othmar,Sheldrick, William S.
p. 14 - 26
(2007/10/03)

Rapid formation of triarylphosphines by microwave-assisted transition metal-catalyzed C-P cross-coupling reactions
(matrix presented) Rapid, direct transition metal-catalyzed C-P(III) cross-coupling reactions were performed by microwave dielectric heating, employing diphenylphosphine and aryl halides/triflates as substrates. Depending on the specific aryl halide/triflate precursor, the highest yields were obtained utilizing heterogeneous or homogeneous Pd or Ni catalysts in DMF or NMP in the presence of KOAc or DABCO as a base.
Stadler, Alexander,Kappe, C. Oliver
p. 3541 - 3543
(2007/10/03)

New non-C2-symmetric phosphine-phosphonites as ligands in asymmetric metal catalysis
Starting from 1,2-dibromobenzene, the synthesis of N,N,N',N'-tetraethyl-[2-(diphenylphosphino)phenyl]phosphonous acid tetraamide is possible in two simple steps. This key compound reacts with a variety of chiral diols such as (R)- and (S)-binaphthol, 1,2:5,6-diisopropylidene-D-mannitol or (1R,2R)-1,2-diphenyl-1,2-ethane diol to form the corresponding non-C2-symmetric phosphine-phosphonite compounds. These ligands react with Rh(COD)2BF4 to form bidentate Rh-complexes which serve as catalysts in the asymmetric hydrogenation of dimethyl itaconate with ee values of up to 88%.
Reetz, Manfred T.,Gosberg, Andreas
p. 2129 - 2137
(2007/10/03)

Novel Syntheses of Mono- and Bisphosphonated Aromatic Phosphanes by Consecutive Pd-Catalyzed P-C Coupling Reactions and Nucleophilic Phosphanylation - X-ray Structure of Ph2P-C6H4-m-PO3Na2 · 5.5 H2O · iPrOH
The triphenylphosphane derivatives 2a and 5, bearing one and two phosphonic ester groups, are accessible in high yields by consecutive Pd-catalyzed P-C coupling reactions of p-bromoiodobenzene with Ph2PH and PhPH2, respectively, and then with diethyl phosphite. Ester hydrolysis yields the highly water-soluble sodium salts of mono- and bisphosphonated triphenylphosphane, 3a and 6, respectively. On reaction of the p- and m-fluorophenylphosphonic diethyl esters 7a, 7b with Ph2PK and subsequent ester hydrolysis the isomeric disodium (diphenylphosphano)phenylphosphonates 3a, 3b were obtained. The X-ray structure of Ph2P(C6H4-m-PO3Na2) · 5.5 H2O · iPrOH (space group Cmc21) has been determined. In the solid state, it forms a layer structure with hydrophilic (PO32-, H2O, iPrOH) and hydrophobic (Ph2P) compartments, in which the PO32- anionic groups are not engaged in coordination of the sodium cations.
Machnitzki, Peter,Nickel, Thomas,Stelzer, Othmar,Landgrafe, Claudia
p. 1029 - 1034
(2007/10/03)

Dinuclear cycloaurated complexes containing bridging (2-diphenylphosphino)phenylphosphine and (2-diethylphosphino)phenylphosphine, C6H4PR2 (R = Ph, Et). Carbon-carbon bond formation by reductive elimination at a gold(II)-gold(II) center
The digold(I) complexes Au2(μ-C6H4PR2)2 [R = Ph (1a), Et (1b)] obtained by treatment of AuBr(PEt3) with o-LiC6H4PR2 undergo addition with halogens or benzoyl peroxide to give metal-metal bonded digold(II) complexes Au2X2(μ-C6H4PR2)2 [R = Ph, Et; X = I (2a, 2b), Br (3a, 3b), Cl (4a, 4b), O2CPh (5a, 5b)], which are structurally similar to the bis(ylide) complexes Au2X2{μ-(CH2)2PR2}2. The benzoate ligands in 5b are monodentate and the gold-gold bond length [2.5243(7) A?] is significantly less than that in the diiodide (2a) [2.5898(6) A?, 2.5960 (A?) for independent molecules], reflecting the trans influences of the axial anionic ligands. The corresponding complexes Au2X2(μ-C6H4PR2)2 [R= Ph, Et; X = O2CMe (6a, 6b), ONO2 (7a, 7b)] are made from 2-4 and the appropriate silver salt. The axial anionic ligands undergo immediate scrambling when solutions of Au2X2(μ-C6H4PR2)2 and Au2Y2(μ-C6H4PR2)2 are mixed. The bridging C6H4PR2 units also scramble rapidly on mixing solutions of Au2X2(μ-C6H4PPh2)2 [X = 1 (2a), Br (3a)] and Au2X2(μ-C6H4PEt2)2 [X = 1 (2b), Br (3b)], but this occurs only slowly for X = Cl and not at all for X = O2CPh, O2CMe, or ONO2. Solutions of the diiodo complexes 2a, 2b and the dibromo complexes 3a, 3b isomerize cleanly to the digold(I) complexes Au2X2(μ-R2PC6H4C6H4PR2) [R = Ph, Lt; X = I (8a, 8b), Br (9a, 9b)] containing 2,2'-biphenylyl(diphenylphosphine) or 2,2'-biphenylyl(diethylphosphine), respectively, as a consequence of a reductive elimination in which a C-C bond is formed at the expense of two Au-C bonds. In 8b the Au-Au separation is 3.167(1) A? and the phenyl rings of the biphenyl unit are almost orthogonal. Qualitatively, the rates of isomerization of Au2X2(μ-C6H4PR2)2 to Au2X2(μ-R2PC6H4C6H4PR2) are in the order R = Ph > Et; X = I > Br >> Cl: isomerization does not occur for X = O2CPh, O2CMe, or ONO2. The rates of thermal isomerization of 2a and 3a are first order in complex, only slightly sensitive to solvent polarity, and, for 2a, inhibited by iodide ion. It is suggested that reversible loss of halide ion initiates aryl group transfer between the gold atoms, thus allowing reductive elimination of Au-C bonds to take place at one center. Treatment of 2a or 3a with an excess of iodine or bromine gives initially digold(III) complexes cis,trans-Au2X4(μ-C6H4PPh2)2 [X = I (14), Br (15)], which are in equilibrium with monomers AuX2(C6H4PPh2) [X = I (16), Br (17)], as shown by 31 P NMR spectroscopy. These species isomerize at room temperature by internal electrophilic cleavage of their Au-C bonds to give stable gold(I) complexes of (2-halogenophenyl)diphenylphosphine, AuX(o-XC6H4PPh2) [X = I (12), Br (11)].
Bennett, Martin A.,Bhargava, Suresh K.,Hockless, David C. R.,Welling, Lee L.,Willis, Anthony C.
p. 10469 - 10478
(2007/10/03)

A novel convenient synthesis of aryl phosphines containing reactive functional groups
A convenient method is described for the preparation of Ph2PC6H4COOH-2 (2) and Ph2PC6H4CHO-2 (5).
Ravindar,Hemling,Schumann,Blum
p. 1453 - 1459
(2007/10/02)

Palladium-Catalyzed Coupling of Aryl Halides with (Trimethylstannyl)diphenylphosphine and (Trimethylsilyl)diphenylphosphine
The palladium-catalyzed reaction of aryl halides with either (trimethylsilyl)diphenylphosphine or (trimethylstannyl)diphenylphosphine gives aryldiphenylphosphines in good yields, under relatively mild conditions (50-70 deg C, benzene).The reaction tolerates a number of functional groups including methyl ethers, esters, ketones, nitriles, anilides, and certain halogens.The nitro and aldehyde groups as well as compounds containing groups such as amino and hydroxyl are not tolerated.
Tunney, S. E.,Stille, J. K.
p. 748 - 753
(2007/10/02)

Carbonylvanadium, -manganese and -molybdenum Complexes of the Ligands o-C6H4EPh2(E'Ph2) (E, E' = P, As, Sb, Bi) and cis-Ph2PCH=CHPPh2
The photo-induced reaction between the complexes (1), η5-C5H5V(CO)4 (2), η5-C5H5Mn(CO)3 (3) or η5-C5H5Mo(CO)3CH3 (4) and the ligands o-C6H4EPh2(E'Ph2) (E = E' = P: a; E = P, E' = As: b; E = E' = As: c; E = P, E' = Sb: d; E = P, E' = Bi: e; E = As, E' = Sb: f) and cis-Ph2PCH=CHPPh2 (g), L, yields - depending on the steric requirement of L - the compounds L ( = cis-V(CO)4(-), cis-CpV(CO)2, CpMn(CO), CpMo(CO)CH3; L = a, b, c, g), L ( = V(CO)5(-), L = d; = CpV(CO)3, L = d, e; = CpMn(CO)2, L = e) or mixtures of L and L (, = V(CO)4,5, L = e, f; , = CpV(CO)2,3, L = f).In the mono-substituted species L coordination (as indicated by the 51V NMR spectra) occurs through EPh2 and E'Ph2, which is explained by a reaction path via a lable chelate 5-ring structure.Shielding of the 51V nucleus decreases in the order g > SbPh2 > PPh2 > AsPh2 > BiPh2 (derivatives of 1) and g > SbPh2 > PPh2 > BiPh2 > AsPh2 (derivatives of 2), and is smaller in the rigid chelates incorporating the o-phenylene ligands than in the more flexible structures of phospha- and arsabutane complexes.This fact is discussed in terms of hindered ?-overlap due to distortion of the EVE angle, which also results in an increase of CO valence force constants in rigid chelates. 31P coordination shifts increase according to dppe a g and arphos b (dppe = Ph2P(CH2)2PPh2, arphos = Ph2As(CH2)2PPh2). 31P NMR spectra of the molybdenum complexes suggest that the basic geometry for 4a and 4b likely is tetragonal pyramidal, while the preferred structure for 4g appears to be the trigonal bipyramid with the ligand in equatorial positions.The crystal and molecular structure of 1a is reported.The complex crystallizes in the space group C2/c (a = 2196.0, b = 1080.1, c = 2022.7 pm, β = 124.6 deg).The most striking result is the small PVP angle of 80.8 (0.2) deg.Optimized methods for the synthesis of the ligands a-f are described; the ligands are characterized by their mass spectra. - Keywords: Carbonylphosphinevanadium, Vanadium-NMR; Phosphorus-NMR
Talay, Ridvan,Rehder, Dieter
p. 451 - 462
(2007/10/02)