Water-Soluble Rhenium Phosphine Complexes Incorporating the PhC(X) Motif (X = O, NH): Structural and Cytotoxicity Studies.

Reaction of [ReOCl(PPh)] or [ReOI(PPh)] with 2,2'-diphenylglycine (dpgH) in refluxing ethanol afforded the air-stable complex [ReO(dpgH)(dpg)(PPh)] (). Treatment of [ReO(OEt)I(PPh)] with 1,2,3-triaza-7-phosphaadamantane (PTA) afforded the complex [ReO(OEt)I(PTA)] (). Reaction of [ReOI(PTA)] with dpgH led to the isolation of the complex [Re(NCPh)I(PTA)]·0.

Bridgehead isomer effects in bis(phosphido)-bridged diiron hexacarbonyl proton reduction electrocatalysts.

The influence of the substitution, orientation and structure of the phosphido bridges in [Fe(CO)(μ-PR)] electrocatalysts of proton reduction has been studied. The isomers e,a-[Fe(CO){μ-P(Ar)H}] (1a(Ar): Ar = Ph, 2'-methoxy-1,1'-binaphthyl (bn')), e,e-[Fe(CO){μ-P(Ar)H}] (1b(Ar): Ar = Ph, bn') were isolated from reactions of iron pentacarbonyl and the corresponding primary phosphine, syntheses that also afforded the phosphinidene-capped tri-iron clusters, [Fe(CO)(μ-CO)(μ-Pbn')] (2) and [Fe(CO)(μ-PAr)] (3(Ar), Ar = Ph, bn'). A ferrocenyl (Fc)-substituted dimer [Fe(CO){μ:μ'-1,2-(P(CHFc)CH)CH}] (4), in which the two phosphido bridges are linked by an o-xylyl group, was also prepared.

A comparison of MOP-phosphonite ligands and their applications in Rh(i)- and Pd(ii)-catalysed asymmetric transformations.

Six chiral MOP-phosphonites have been synthesised and compared via experimental and computational methods in an effort to quantify their differing structural and electronic profiles. They were found to be electron-poor ligands in comparison to their arylphosphine analogues and have a larger trans influence in square planar Pt(ii) complexes. Four [Rh(L)(η:η-cod)Cl] complexes were synthesised and characterised by NMR, HRMS and X-ray crystallography.

Structurally optimised BODIPY derivatives for imaging of mitochondrial dysfunction in cancer and heart cells.

The structural features required for mitochondrial uptake of BODIPY-based optical imaging agents have been explored. The first derivatives of this class of dyes shown to have mitochondrial membrane potential-dependent uptake in both cancer and heart cells have been developed.

The design of second generation MOP-phosphonites: efficient chiral hydrosilylation of functionalised styrenes.

A series of enantiopure MOP-phosphonite ligands, with tailored steric profiles, have been synthesised and are proven to be very successful in high-yielding, regio- and enantioselective catalytic hydrosilylation reactions of substituted styrenes, affording important chiral secondary alcohols.

Zirconium-catalyzed intermolecular hydrophosphination using a chiral, air-stable primary phosphine.

Catalytic hydrophosphination of alkenes using a chiral, air-stable primary phosphine, (R)-[2'-methoxy(1,1'-binapthalen)-2-yl]phosphine, (R)-MeO-MOPH2, proceeds under mild conditions with a zirconium catalyst, [κ(5)-N,N,N,N,C-(Me3SiNCH2CH2)2NCH2CH2NSiMe2CH]Zr (1), to selectively furnish anti-Markovnikov, air-stable secondary phosphines or tertiary phosphines with slight modification of the protocol. An intermediate in the catalysis, [(N3N)Zr(R)-MeO-MOPH] (4), was structurally characterized.

Re and (99m)Tc complexes of BodP3--multi-modality imaging probes.

A fluorescent tridentate phosphine, BodP3 (2), forms rhenium complexes which effectively image cancer cells. Related technetium analogues are also readily prepared and have potential as dual SPECT/fluorescent biological probes.

BR2BodPR2: highly fluorescent alternatives to PPh3 and PhPCy2.

The syntheses of highly fluorescent analogues of PPh3 and PhPCy2 based on the Bodipy chromophore are described. The ligands have been incorporated into two- to four-coordinate group 11 metal complexes. The synthesis, characterisation and photophysical properties of the novel ligands and their metal complexes are reported; many of these compounds have also been characterised by single-crystal X-ray diffraction.

Chiral MOP-phosphonite ligands: synthesis, characterisation and interconversion of η1,η6-(σ-P, π-arene) chelated rhodium(I) complexes.

The synthesis of rhodium(I) and iridium(I) complexes of chiral MOP-phosphonite ligands is reported. The full characterisation of η(1),η(6)-(σ-P, π-arene) chelated 18VE rhodium(I) complexes reveals hemilabile binding on the arene which has been quantitatively analysed.

Naphthoxaphospholes as examples of fluorescent phospha-acenes.

Seven new fluorescent 2-R-naphtho[2,3-d]oxaphospholes (R-NOPs) (4a–g; R = tBu (a), Ad (b), C(6)H(5) (c), 4-MeC(6)H(4) (d), 4-ClC(6)H(4) (e), 4-BrC(6)H(4) (f ), 4-MeOC(6)H(4) (g)), have been synthesized by cyclocondensation reactions of benzimidoyl chlorides with 3-phosphino-2-naphthol (3). The compounds were characterized by multinuclear NMR, UV-vis, and fluorescence spectroscopy. Compounds 4a–d and 4g were characterized by cyclic voltammetry experiments.

Air-stable, highly fluorescent primary phosphanes.

Light without fright: a synthetic route to fluorescent primary phosphanes (RPH(2)) that are resistant to air oxidation both in the solid state and in chloroform solution is described. These versatile precursors undergo hydrophosphination to give tripodal ligands and subsequently fluorescent transition-metal complexes.

MOP-phosphonites: a novel ligand class for asymmetric catalysis.

Chiral phosphonite ligands (S,R(b))-5a, (S,S(b))-5b, (R,R(b))-6a and (R,S(b))-6b are introduced, comprising a MOP-type backbone with a binol-based binaphthyl group bound to the phosphorus. Their reaction with [Pd(η(3)-C(4)H(7))Cl](2) affords η(3)-methallylpalladium chloride complexes 7a/b and 8a/b which have been isolated and structurally characterised. Solid-state and solution studies indicate subtle differences in their coordination behaviour, which ultimately affects their efficacy in the asymmetric hydrosilylation of styrene.

Taming functionality: easy-to-handle chiral phosphiranes.

Enantiopure chiral phosphiranes possessing a binaphthyl backbone demonstrate remarkable thermal stability, are highly resistant to air-oxidation and are effective ligands in catalytic asymmetric hydrosilylations.

A re-evaluation of the electrophilic substitution reactions of the Ramirez ylide.

Cyclopentadienylidenetriphenylphosphorane (the Ramirez ylide), unexpectedly and contrary to a number of earlier reports, has been shown to be like pyrrole in undergoing electrophilic substitution on the cyclopentadienide ring at either the 3- or the 2-position, depending on the electrophile. Formylation under Vilsmeier conditions and addition of tetracyanoethylene occurs at the 3-position, while activated acetylenes and the nitrosyl electrophile substitute at the 2 position. The 3-formylated product was reduced to the 3-methyl derivative and it also reacted under Knoevenagel conditions to give a number of novel condensation products.

Water-soluble hydroxyalkylated phosphines: examples of their differing behaviour toward ruthenium and rhodium.

The reaction of P(CH2OH)3 (I) and P(C6H5)(CH2OH)2 (II) with RuCl3 in methanol eliminates two equivalents of formaldehyde to yield the mixed tertiary and secondary phosphine complexes all-trans-[RuCl2(P(CH2OH)3)2(P(CH2OH)2H)2] (1) and [RuCl2(P(C6H5)(CH2OH)2)2(P(C6H5)(CH2OH)H)2] (2), respectively. There is a high degree of hydrogen-bonding interactions between the hydroxymethyl groups in 1 and 2, although the phenyl groups of the latter reduce the extent of the network compared to 1. The generation of these mixed secondary and tertiary phosphine complexes is unprecedented.

[(E)- and [(Z)-2-[alpha,beta-bis(methoxycarbonyl)vinyl]cyclopentadien-1-ylidene]triphenylphosphorane.

The Ramirez ylide undergoes electrophilic substitution with dialkyl acetylenedicarboxylates, yielding a mixture of the Z and E adducts. The crystal structure analyses of the two adducts formed using dimethylacetylene, viz. dimethyl (E)- and (Z)-1-[2-(triphenylphosphoranylidene)cyclopentadien-1-yl]ethylenedicarboxylate, both C(29)H(25)O(4)P, explain an unusual chemical shift observed for the vinyl H atom of the Z adduct, which had previously precluded a definitive assignment of the isomers.

A novel azulene synthesis from the Ramirez ylide involving two different modes of its reaction with activated alkynes.

The Ramirez ylide undergoes electrophilic substitution with acetylenedicarboxylates to form Z and E adducts. The latter can react by cycloaddition with another equivalent of the alkyne to provide a new route to novel tetra-substituted azulenes, which show interesting bond localisation and crystal packing effects.