The release of nitro groups from neutral mer-triamine-trinitrocobalt(III) complexes [triamine = 2,2-tri (dien) (1), 2,3-tri (2), 3,3-tri (dpt) (3), (NH,)(en) (4), (NH3)(tn) (5)], in the presence of greater than or equal to 10 fold excess hydroxide ion, proceeds in two distinct, pseudo-first-order, steps. For both steps, plots of k(obs) vs [OH-] are linear in the range 0.025 less than or equal to [OH-] less than or equal to 1.0 M with zero intercept. For the tridentate triamines, the first step corresponds to the formation of mer-[Co(OH)(NO2)(2)(triamine)] and the final product is mer-[Co (OH)3(triamine)]. As with mer-[Co(NO2)(3)(NH3)(3)], the ammine complexes, 4 and 5, form precipitates at long reaction times. The classic base hydrolysis behaviour of those neutral complexes suggests that ion-pairing is not mechanistically important and the data can be interpreted in terms of the conventional S(N)1CB (DCB) mechanism. The crystal structures of 2, 3, 5 and [Co(NO2)(3)(Medpt)] (6) have also been determined, confirming the mer- configuration.

The preparation, isolation and characterisation of 1,3-bis(diphenylphosphino)indene (1) from indene and chlorodiphenylphosphine is described. The reaction of 1 with selenium gives the diselenide adduct 1,3-bis(diphenylselenophosphino)indene (2) which was characterised crystallographically. Deprotonation of 1 and treatment with ferrous chloride gives the unstable tetraphosphine complex bis(1,3-bis(diphenylphosphino)indenyl)iron(II) (3). Complex 3 decomposes to the diphosphine complex bis(1-diphenylphosphinoindenyl)iron(II) (4) via replacement of one diphenylphosphine substituent per indenyl ligand by a hydrogen atom. Complex 4 was also prepared by treatment of two equivalents of 1-diphenylphosphinoindenide with ferrous chloride. The heterobimetallic complex tetracarbonyl(bis(1-diphenylphosphinoindenyl)iron(II))molybdenum(0) (5) was also prepared and crystal structures of both the meso (5a) and C2-symmetric racemic (5b) isomers are reported.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSelective Oxidative Addition at Single Centers in Triiridium Clusters. Crystal and Molecular Structures of One- and Two-Fragment Addition Products, [Ir3(.mu.-PPh2)3(CO)4(t-BuNC)3(CH3)]I and [Ir3(.mu.-PPh2)3(CO)3(dppm)I(OH)].cntdot.CH2Cl2Fathi Asseid, Jane Browning, Keith R. Dixon, and Neil J. MeanwellCite this: Organometallics 1994, 13, 3, 760–762Publication Date (Print):March 1, 1994Publication History Published online1 May 2002Published inissue 1 March 1994https://pubs.acs.org/doi/10.1021/om00015a007https://doi.org/10.1021/om00015a007research-articleACS PublicationsRequest reuse permissionsArticle Views40Altmetric-Citations11LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Complexes of the anionic ligand, [C(PPh2)(P(S)Ph2)2]−, are readily prepared under mild conditions by reactions of CH(PPh2)(P(S)Ph2)2, in the presence of base (NHEt2), with chlorobridged complexes, [M2Cl2(cod)2], M  Rh or Ir, cod = cycloocta-1,5-diene, [Pt2Cl4(PEt3)2], and [Pt2Cl2(MeOcod)2], MeOcod = 8-methoxy-cyclooct-4-ene-1-yl. The products are [M(cod){C(PPh2)(P(S)Ph2)2-P,S}], [PtCl(PEt3){C(PPh2)(P(S)Ph2)2-P,S}], and [Pt(MeOcod){C(PPh2)(P(S)Ph2)2-P,S}] respectively, and the platinum complexes are both mixtures of the two possible isomers. Subsequent reactions of [Rh(cod){C(PPh2)(P(S)Ph2)2-P,S}] with tBuNC followed by oxidative addition of I2 or benzyl bromide give [Rh(tBuNC)2{C(PPh2)(P(S)Ph2)2-P,S}], and isomeric mixtures of [RhI2(tBuNC)2{C(PPh2)(P(S)Ph2)2- P, S}] and [RhBr(Bz)(tBuNC)2{C(PPh2)(P(S)Ph2)2-P, S}].

Reactions of the chloro-bridged complexes, [M2Cl2(cod)2], M  Ir or Rh, with CHR(P(S)Ph2)2, R  H or Me, provide a synthetic route to the cations, [M(cod){CHR(P(S)Ph2)2-S,S}]+, which are isolated as fluoroborate or perchlorate salts. Treatment of these products with sodium hydride results in facile deprotonation to the neutral complexes, [M(cod){CR(P(S)Ph2)2-S,S}], and when R  H, the neutral complexes are also accessible via reactions of [M2Cl2(cod)2] with Li[CH{P(S)Ph2)2]. The complexes, [Ir(cod){CH(P(S)Ph2)2-S,S}], and [Rh(cod){CH(P(S)Ph2)2-S,S}], crystallize in the P1 (No. 2) space group (Z = 2) with respective unit cells: a = 11.570(4), b = 15.122(2), c = 9.919(3) Å, α = 79.86(4), β = 64.87(3), γ = 97.94(4)°; and α = 11.571(16), b = 15.078(2), c = 9.869(2) Å, α = 100.16(1), β = 64.97(1), γ = 82.10(1)°. Both structures consist of puckered 6-membered rings formed by coordination of the disulfide ligands via two sulfur atoms to the metal center. The rings lie in distorted boat conformations with the prows occupied by one sulfur and one phosphorus and the metal atoms in one side.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and phosphorus-31 NMR spectroscopy of trinuclear, phosphido-bridged iridium and rhodium clusters. Crystal and molecular structures of [M3(.mu.-PPh2)3(CO)nL2] (M = Ir or Rh, n = 3, L2 = 1,2-bis(diphenylphosphino)methane; M = Ir, n = 5, L = tert-BuNC)David E. Berry, Jane Browning, Khashayar Dehghan, Keith R. Dixon, Neil J. Meanwell, and Andrew J. PhillipsCite this: Inorg. Chem. 1991, 30, 3, 396–402Publication Date (Print):February 1, 1991Publication History Published online1 May 2002Published inissue 1 February 1991https://pubs.acs.org/doi/10.1021/ic00003a009https://doi.org/10.1021/ic00003a009research-articleACS PublicationsRequest reuse permissionsArticle Views85Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Reaction of [Ir2(cyclooctene)4Cl2] with CO, NHEt2, and PHPh2 provides a synthetic route to the trinuclear, phosphido-bridged iridium clusters [Ir3(mu-PPh2)3(CO)nL2] (n = 3, L = CO or PPh3, L2 =bis(diphenylphosphino)methane (dppm); n = 5, L = t-BuNC). The CO andPPh3 complexes are analogues of previously known rhodium derivatives, and rhodium analogues of the dppm and t-BuNC complexes are also reported. [Ir3(mu-PPh2)3(CO)3(dppm)] (I) and [Rh3(mu-PPh2)3(CO)3(dppm)] (II) crystallize in the Pnma space group (Z = 4) with the following respective unit cell dimensions: a = 23.963 (5) angstrom, b = 24.970 (5) angstrom, c = 11.080 (2) angstrom; a = 24.031 (6) angstrom, b = 25.069 (9) angstrom, c = 11.117 (4) angstrom. [Ir3(mu-PPh2)3(CO)5(t-BuNC)2] (III) crystallizes in the P2(1)/n space group (Z = 4) with a = 23.015 (4) angstrom, b = 20.197 (6) angstrom, c = 11.849 (5) angstrom, and beta = 92.19 (4)degrees. The structures of I and II consist of approximately equilateral triangles of metal atoms (average M-M distances 2.78 (Ir) and 2.79 angstrom (Rh)), with the CO and two PPh2 ligands lying approximately in the M3 plane. The third PPh2 bridge is approximately perpendicular to this plane, linking the two basal metal atoms, which are also bridged by the dppm ligand. In contrast, the structure of III has all three PPh2 bridges approximately in the M3 plane with the t-BuNC ligands added approximately perpendicular to this plane at the apical iridium. The Ir-Ir distances are much longer, averaging 3.23 angstrom. Complete analyses of P-31 NMR spectra are reported for I-III and for IV, the Rh analogue of III. The phosphido bridge shifts reflect the changes in metal-metal distances, with I and II strongly deshielded (by 80-240 ppm) relative to III and IV. There is also a general reduction in the one-bond Rh-P coupling constants in the 50-electron cluster, IV relative to the 46-electron cluster, II.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactivity of coordinated [Ph2PCHP(S)Ph2]- and [Ph2P(S)CHP(S)Ph2]-: two-center, regiospecific reactivity in rhodium and iridium complexes and formation of a disubstituted methylene bridge between platinum atomsJane. Browning, Keith R. Dixon, and Robert W. HiltsCite this: Organometallics 1989, 8, 2, 552–554Publication Date (Print):February 1, 1989Publication History Published online1 May 2002Published inissue 1 February 1989https://doi.org/10.1021/om00104a043RIGHTS & PERMISSIONSArticle Views93Altmetric-Citations34LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (395 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Reactions of the bisphosphine monochalcogenides, [Ph 2 PCH 2 P(Y)R 2 ], Y = O, S, or Se, R = Ph, Pr i , or Bu t , with the chloro-bridged dimers [M 2 Cl 4 (PR′ 3 ) 2 ], M = Pd or Pt, R′ = Et or Bu n , in the presence of either NaClO 4 or NaBF 4 yield perchlorate and fluoroborate salts of the complex cations cis- and trans-[PtCl(PR′ 3 ){Ph 2 PCH 2 P(Y)R 2 }] + . In many cases both cis and trans isomers (defined by the relative orientation of the two M—P bonds) are obtained and the precise isomer distribution is a sensitive function of the substituents. Corresponding neutral complexes, cis- and trans-[PtCl(PR′ 3 ){Ph 2 PCHP(Y)R 2 }], can be synthesized either by deprotonation of the cations using NaH or by use of the salts Li[Ph 2 PCHP(Y)R 2 ] in the initial bridge cleavage reactions. These and related complexes are characterized by complete 13 C, 31 P, 77 Se, and 195 Pt NMR studies and by two crystal structure determinations. The complexes I, trans-[PtCl(PEt 3 ){Bu t 2 PCH 2 P(O)Me 2 }][ClO 4 ], and II, trans-[PtCl(PEt 3 ){Ph 2 PCH 2 P(S)Bu t 2 }][ClO 4 ], crystallize in the monoclinic space group P2 1 /c, respective cell dimensions: a = 15.579(2), b = 13.590(3), c = 13.578(1) Å;β= 105.96(1)°; and a = 14.002(4), b = 16.366(5), c = 15.524(5) Å; β = 106.01 (3)°. Complete X-ray diffraction studies show that both complexes contain closely square planar platinum centres with the R 2 PCH 2 P(Y)R′ 2 ligands coordinated via phosphorus and the Y atom so as to form five-membered chelate rings. The molecular dimensions suggest that the bond to sulphur is stronger than that to oxygen and exerts a larger trans influence.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhosphorus-31 and platinum-195 NMR studies and the crystal and molecular structure of chloro(triethylphosphine)[tris(diphenylphosphinothioyl)methyl]platinum(II) ([PtCl(PEt3){C(PPh2S)3}]), an S,S-bonded chelate with dynamic stereochemistry controlled by one labile and one inert platinum-sulfur bondJane Browning, Kathryn Anne Beveridge, Gordon William Bushnell, and Keith Roger DixonCite this: Inorg. Chem. 1986, 25, 12, 1987–1992Publication Date (Print):June 1, 1986Publication History Published online1 May 2002Published inissue 1 June 1986https://pubs.acs.org/doi/10.1021/ic00232a017https://doi.org/10.1021/ic00232a017research-articleACS PublicationsRequest reuse permissionsArticle Views60Altmetric-Citations24LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

AbstractThe complexes (III) and (V) are prepared by bridge‐cleavage reactions of the appropriate chloro‐bridged dimers (I) and (IV) with the ligand (II), which spontaneously deprotonates in these reactions.

[PtCl(PEt3)(Ph2PCHPPh2)], a complex containing the bis(diphenylphosphino)- methanide ligand, has been synthesized by reaction of NaH with [PtCl(PEt3)- (Ph2PCH2PPh2)]+ and characterized by 31P NMR and X-ray cystallography.

AbstractDie Titelverbindungen (III) wurden durch Reaktion der Komplexsalze (I) mit den Hg‐ Verbindungen (II) erhalten.

The crystal structure of a nickelahexakis(trifluoromethyl)cycloheptatriene, C18H18F18NiO6P2 has been determined. The compound crystallizes in the orthorhombic space groupPbcn, witha = 17.355(5),b = 11.014(3),c = 15.026(5) Å andZ = 4. The molecular symmetry is 2(C2). X-ray intensity data were collected by counter methods, using MoKα radiation, and least-squares refinement led toR = 0.050 for the 804 reflexions for which. ¦F0¦2 >2σ(¦F0¦2). The [C2(CF3)2]3 ligand is attached to the nickel atom by σ-bonds from the two terminal carbon atoms (Ni—C = 1.96 Å) and by a η-bond from the two central (double-bonded) carbon atoms (Ni—C = 2.04 Å). This is the first example of the coordination to a transition metal of an olefinic group which is also part of a chelate.

Reaction of [Pt(trans-stilbene)(PEt3)2] with C6(CF3)6 affords a complex [Pt{C6(CF3)6}(PEt3)2], shown by variable temperature 19F n.m.r. spectroscopy to be a fluxional molecule. Treatment of the related nickel complexes [Ni{C6(CF3)6}L2](L = AsMe2Ph or P(OMe)3) with an excess of CF3CCCF3 yields a new kind of complex: a hexakis(trifluoromethyl)nickelacyclohepta-cis,trans,cis-triene. Reaction of [Pt{C2(CF3)2}(PEt3)2] with excess of hexafluorobut-2-yne proceeds more slowly to afford a monophosphine substituted hexakis(trifluoromethyl)platinacyclohepta-cis,trans,cis-triene, which with Ph2PCH2CH2PPh2 gives a complex isostructural with the nickel systems.

The crystal structure of bis(tiethylphosphine)(hexakis(trifluoromethyl)benzene) platimum, C24H30F18P2Pt, has been determined. The crystals are monoclinic: space groupP21/n,a = 9.937(6),b = 30.89(1),c= 11.398(8) Å, β = 117.15(3) ° andZ = 4. X-ray data were collected by counter methods using MoKα radiation, and least-squares refinement led toR = 0.057 for the 2154 independent reflexions for which ¦F0¦2> 3σ(¦F0¦2). The molecule has a 1,2-hapto structure, with the platinum atom bonded to only two carbon atoms of the hexakis(trifluoromethyl)benzene ring. The planarity of this ring is destroyed as a result of the coordination and there is an alternation of long and short bonds around the ring. The mean Pt—C bond length is 2.14(2) Å.