24??????inorganic and organometallic polymers

24 Inorganic and organometallic polymers

Derek P. Gates

Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver,BC, Canada V6T 1Z1

1 Introduction

The preparation and study of polymers composed partially or entirely of inorganicelements is an area which attracts interest from researchers in main group, organo-metallic, polymer, and materials chemistry. Researchers involved in designing newinorganic macromolecules are motivated by the challenges associated with developingnew synthetic methodologies, and the prospect of unusual properties and thuspossible speciality applications for these materials.

This review provides an overview of developments in the broad field of inorganicand organometallic polymer science during 2001, and continues in the tradition estab-lished by Ian Manners and Michael Turner in previous articles in this series.1–4 Thisarticle is subdivided into three sub-sections. The first two discuss aspects of the chem-istry of main group-element containing polymers, whilst the last section provides anoverview of recent developments in the rapidly expanding area of d-block element-containing macromolecules. In this article emphasis is placed on the synthesis andstudy of linear polymers possessing inorganic elements within the main chain. How-ever, in some instances novel polymers with inorganic elements in the side-groupstructure will also be highlighted.

In the past year a number of important reviews and highlights have appeared in thearea of inorganic polymer chemistry. Of particular significance is the publication of atextbook written by Ronald Archer entitled Inorganic and Organometallic Polymers.5

This excellent book is the first comprehensive text published in the field since thewidely cited Inorganic Polymers, which was published in 1992.6 Archer’s book pro-vides a broad and general coverage of the field, and therefore promises to be aninvaluable resource, particularly for new researchers in the field.7,8 A piece written byIan Manners appeared in Science which highlights recent progress in the exciting areaof metal containing polymers and offers an outlook for the future.9 A fascinating andcomprehensive review of the development of the silicones industry has been writtenby Dietmar Seyferth.10 This historical account is likely to be of significant interest toresearchers with interests in inorganic or polymer chemistry, and also chemical educ-ation. In addition, to those pointed out in this introductory section, a number of otherimportant reviews have been published over the past year, and will be mentioned inlater sections of this report.

DOI: 10.1039/b109718k Annu. Rep. Prog. Chem., Sect. A, 2002, 98, 479–492 479

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View Article Online / Journal Homepage / Table of Contents for this issue

http://dx.doi.org/10.1039/b109718k

http://pubs.rsc.org/en/journals/journal/IC

http://pubs.rsc.org/en/journals/journal/IC?issueid=IC002098

2 Group 14 element-containing polymers: polysiloxanes (silicones),polysilanes, and others

The established fields of polysiloxanes and polysilanes continue to generate excitingnew results. A note on the nomenclature of silicone polymers used in the ChemicalAbstracts Services (CAS) databases may be of practical use.11 A review has beenpublished which highlights the preparation and applications of linear and crosslinkedsilicones and the applications for these materials as adhesives and sealants.12 Thesynthesis of stereoregular silicon-containing polymers has been reviewed.13 Thesynthesis, reactions and possible applications of siloxane and carbosiloxane baseddendrimers has been reviewed.14

In a study by Hooper, West and co-workers a series of novel ethylene glycol substi-tuted polysiloxanes 1 (m = 1–7) [Mw (PDI) = 7,300 (1.25) (m = 1) to 25,000 (1.20)(m = 7)] were prepared by condensation of the functionalized dichlorosilanes, whichwere obtained from H2SiCl2 using hydrosilylation.15 The amorphous polymers showedglass transitions (T g’s) between �55 and �70 �C. Upon doping with lithium bis-((trifluoromethyl)sulfonyl)imide these double-comb polymers showed conductivitiesin the range of 2.8 × 10�5 to 4.5 × 10�4 S cm�1 with the maximum conductivityoccurring for 1 (m = 5) at a doping level of 32 : 1 (O : Li). These results were found tobe consistent with the analogous doped polyphosphazene systems.

The successful cationic ring-opening polymerisation (ROP) of the eight-memberedring system 2 to yield poly(dimethylsilylenemethylene-co-dimethylsiloxane) 3, anexample of a regularly alternating copolymer of a polysiloxane and a polycarbosilane,has been reported.16 High molecular weights [Mn (PDI) = 50,000 (1.4–1.8)] for thisnew class of polymer were estimated using GPC. DSC analysis of 3 showed a glasstransition of �106 �C which is in between that of poly(dimethylsiloxane) (�127 �C)and poly(dimethylsilylenemethylene) (�100 �C). Interestingly, the ring-opening poly-merisation of 2 was not successful with anionic initiators, nor could the analogousethyl substituted heterocycle be induced to undergo ROP.

The anionic ring-opening polymerisation of 2,2-divinyl-4,4,6,6-tetramethyl-cyclotrisiloxane yields polymers with a regular microstructure, however broadmolecular weight distributions (PDI = 1.3 – 2.0) suggest that this was not a living

480 Annu. Rep. Prog. Chem., Sect. A, 2002, 98, 479–492

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polymerisation.17 The mechanisms of both the cationic and anionic polymerisationswere discussed. Interestingly, the T g of poly(2,2,-divinyl-4,4,6,6-tetramethyltrisil-oxane) (�128 �C) is lower than that of poly(dimethylsiloxane) (�124 �C). Per-fluoroalkyl groups can be introduced into the polymers by a post-polymerisationhydrosilylation with HSi(Me)2CH2CH2CF3 or HSi(Me)2(CF2)5CF3 using Karstedt’scatalyst.

A catalytic route has been developed to prepare alkoxy-substituted silicones usingdehydrogenative oxidation of poly(methylhydrosiloxane) 4 catalyzed by Wilkinson’scatalyst.18 With 2% loadings of [Rh], high yields of eight new poly(methylalkoxy-siloxanes) (ca. 90 %) were obtained (e.g. 5), and GPC analyses were consistent with nosignificant degradation of the polymer. In a separate study, dehydrogenative silyl-ation condensation copolymerisation of α,ω-dihydridooligodimethylsiloxanes witho-quinones has been accomplished using [RuH2(CO)(PPh3)3] as the catalyst.19 Thepresence of aromatic units in the backbone of polymer 6 leads to good thermalstability (10% weight loss to 400 �C) and imparts luminescent properties whilstmaintaining fairly low T g’s.

The anionic polymerisation of 1,3,5-tris(trifluoropropylmethyl)cyclotrisiloxaneunder emulsion polymerisation conditions using NaOH as initiator gives high yieldsof polysiloxane with molecular weights between 2,000 and 30,000 g mol�1.20 Kineticstudies revealed that during the first stage the anionic ROP is under kinetic control,whereas condensation and back-biting reactions are involved in the second stage ofpolymerisation.

A review has appeared which highlights recent progress on stannasiloxane rings andpolymers.21 These interesting species are formally heavy element congeners of

Annu. Rep. Prog. Chem., Sect. A, 2002, 98, 479–492 481

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siloxanes where one or more of the silicon atoms are replaced by tin. Unfortunately,the heterocyclic compounds (6-, 8-, and 10-membered rings) are often favoured overthe linear polymers. However, in a few cases poly(stannasiloxanes) are isolable in thesolid-state and can be characterised by X-ray diffraction but depolymerise in solution.

The anionic block copolymerisation of masked disilene 7 with triphenylmethylmethacrylate in the presence of (�)-sparteine yields 1 : 1 block copolymer 8 [Mn =1.0 × 104; PDI = 1.5].22 The presence of (�)-sparteine induces optical induction in theacrylate block to give a one-handed helical screw, while the silane chain adopts arandom conformation. Remarkably, an abrupt shift in λmax (310 to 340 nm) in the UVabsorption spectra of 8 was observed at �20 �C and positive Cotton signals wereobserved at 340 nm in the CD spectra. These results suggest that the polysilane blockis induced to a one-handed helical sense by the acrylate block, and this helicalprogramming is reversible as the temperature is varied.

A novel application for achiral polysilane 9 in the transfer and amplification ofchiral molecular information has been developed.23 This simple method for chiraldetection takes advantage of the weak interactions between chiral guest alcohols andthe ether groups in 9 which are amplified by the formation of polymer aggregates. Thesigns of the bisignate Cotton effects in the CD spectra are sensitive to the absoluteconfiguration of a variety of substrate alcohols. Helical polysilanes 10 and 11 pre-pared using the Wurtz coupling route were studied by CD and polymer 10 showedswitchable helicity with changes in temperature whereas polymer 11 did not switchpreferential screw-sense over the temperature range �83 to �80 �C.24 For polymer 10three distinct switching regions were observed which were interpreted as super-posed right- and left-handed helicities. The compensation temperature (T c) was highlysensitive to the structure of the solvent, suggesting that these polysilanes may findapplication in molecular recognition.


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A substantial amount of research has been conducted on rigid helical polysilanes inan effort to understand the conformational properties of these novel polymers.25–29

For instance, a remarkable dependence of the stiffness of polysilanes bearing chiralside-chains was observed for poly{n-hexyl-[(S)-2-methylbutyl]silylene)} 12 andpoly{n-hexyl-[(S)-3-methylpentyl]silylene)} 13, with the former adopting a rodlikestructure and the latter being more like a random coil.25,26 In addition, studies in dilutesolution of the conformational transitions of polymer 13 of various molecularweights have shown that the correlation lengths of the helix are much shorter than inpolyisocyanates, and that helix reversal is the dominant process in these polysilanes.27

The thermochromic properties of poly(di-n-hexylsilane) and poly(di-n-octylsilane)have been studied.30,31 Of particular significance is the discovery of a third absorptionband at 368 nm (band III) upon cooling an aged solution (5 days) of poly(di-n-hexylsilane) in addition to band I (320 nm) and band II (357 nm).30 The three bandshave been assigned to a disordered form of the polymer (band I), a transoid helicalform with Si–Si–Si–Si torsional angles near 165� (band II), and band III has beenattributed to an ordered state with near anti (trans) conformation. The structure andchain conformation of three asymmetrically substituted poly(methyl-n-alkylsilanes)have been studied using X-ray diffraction and UV absorption spectroscopy.32

A convenient method for the synthesis of a wide range of previously inaccess-ible heteroatom-substituted polysilanes 16 has been developed through halide-substitution reactions of perchloropolysilane 15 with a variety of alcohols.33 Polymer15 can conveniently be prepared from the ROP of 14.

Isolated, controlled diameter and length nanowires have been prepared using high-energy ion beam irradiation of thin films of poly(methylphenylsilane).34 Refluxing lowmolecular weight poly(methylsilane) (Mw = 1780 g mol�1) at temperatures between


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423 and 723 K gave cross-linked polymers which serve as precursors to silicon–carbidematerials.35 The chemical transformations involved in the pyrolysis of thin films ofpoly(methylsilane) and poly(dimethylsilane) in the presence of ammonia to yieldα-Si3N4 have been studied by infrared spectroscopy.36

A highlight of recent developments in the synthesis of carbosilane dendrimers hasbeen written by Kriesel and Tilley.37 Studies of the electronic structure of polycarbo-silane [(SiMe2)2CH2]n by UV photoelectron spectroscopy suggest that despite thepresence of carbon atoms in the backbone, there is still σ-conjugation through thebackbone.38 The structures of polycarbosilanes [SiR2CH2]n (R = Et, nPr, nBu, nPentyl,nHex) have been examined using X-ray and electron diffraction which revealed a 41

helical structure for these materials.39,40

The synthesis and ring-opening polymerisation of the spirocyclic silacyclobutane17 has been accomplished using Karstedt’s catalyst, and the polymer 18 was charac-terised by solution and solid-state NMR spectroscopy.41 Unfortunately, GPC analysisof 18 was not possible due to moisture sensitivity, however dynamic light scattering ofthe soluble fraction showed a hydrodynamic radius of <1 nm (Mw ca. 3000). Attemptsto polymerise ethylene using 18 and methylaluminoxane (PMAO-IP) were successful;however, unfortunately low activities were observed.

3 Group 15 element-containing polymers: polyphosphazenes, andother main group element-containing macromolecules

The chemistry and applications of polyphosphazenes have continued to attract wide-spread interest in both academic and industrial research laboratories over thepast year. A detailed review on phosphazene research with over 300 references hasbeen published which highlights the cyclic and polymeric chemistry of phos-phazenes.42 An account of the synthesis of polymers containing cyclophosphazeneshas also appeared.43

An interesting application for poly(methylphenylphosphazene) has been dis-covered. The polymer can be employed in the preparation of well-defined gold nano-particles where stabilization is believed to occur through the nitrogen lone pair ofelectrons in the polyphophazene backbone.44 The nanocomposites are stable forseveral months at temperatures below the T g (37 �C) and transmission electron micro-scopy (TEM) images indicate that the gold nanoparticles (particle size 5–7.5 nm) areuniformly distributed throughout the polymer. Some degree of aggregation of thegold nanoparticles is observed above T g or in solution.

The influence of solvent, temperature, concentration and initiator on the cationiccondensation polymerisation of phosphoranimines 19 has been studied by Allcock


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and co-workers.45 Interestingly, polymerisations conducted in toluene, dioxane orbenzene were found to proceed faster than those in chlorinated solvents. In addition,following initial slow polymerisation rates due to precipitation of short-chain salts 20(n = 1, 2, etc.), upon redissolution the propagation followed pseudo-first-order kineticsto give controlled molecular weight 20 (ca. 105 g mol�1) with narrow polydispersities(<1.3). The controlled cationic polymerisation of phosphoranimines has also beenused to access a micellar amphiphilic diblock copolyphosphazene containing a hydro-philic block of {N��P[(OCH2CH2)2OCH3]2}n and a hydrophobic block of {N��PPh-(OCH2CH2)2OCH3}n.

46 The scope of this reaction has also been extended to preparecontrolled molecular weight (104–105 g mol�1) di- and tri-block copolymers containingpolyphosphazenes and polysiloxanes.47 Poly(phosphazene-ethylene oxide) blockcopolymers have been prepared using a similar strategy.48 These materials werestudied for their potential use as solid polymer electrolytes and showed conductivitiesafter complexation with LiOTf between 7.6 × 10�6 and 1.0 × 10�4 S cm�1.

Allcock and coworkers have developed novel methods to employ the olefinmetathesis reaction in the synthesis of new phosphazene polymers. The living cationicpolymerisation of phosphoranimine was successfully terminated with a norbornenylfunctionality yielding a monotelechelic polyphosphazene.49 The ring-opening meta-thesis polymerisation (ROMP) of end-functionalised polyphosphazene and nor-bornene using Grubbs catalyst afforded graft copolymers 21 (R = CH2CF3) withmolecular weights of 104–106 and T g’s in the range 30–55 �C. In a separate study, theapplication of acyclic diene metathesis (ADMET) polymerisation has been used tointroduce cyclophosphazene moieties into an organic polymer backbone.50 Theseinteresting organic–inorganic hybrid polymers 22 (a R = OC6H4OCH2Ph, b R = OPh,c R = O(CH2CH2O)2Me) were found to have high molecular weights [Mn= 32,000(22a), 32,800 (22b), 45,500 (22c)] and the samples were analysed by DSC which for 22crevealed a T g at �75 �C and a T m at �55 �C. Of note, these systems are amongst thelargest species to be polymerised using olefin methathesis.

Partially thiophenol-substituted polyphosphazenes have been prepared by the reac-tion of [NPCl2]n with HSC6H4R (R = H or Br) in the presence of Cs2CO3.

51 Loadingsof thiophenol between 25 and 30% were obtained and the remaining P–Cl bonds were


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replaced by aryloxide. Efficient routes have been developed to attach dialkyl-phosphonate groups to the aryl side-groups in poly(aryloxyphosphazenes).52 Detailedrheological studies have been carried out on the interesting polymer poly(2,2�-dioxybiphenylphosphazene).53 A size exclusion chromatography multi-angle laserlight scattering study of poly(bis(piperidino)phosphazene) revealed that anomaloussolution behaviour can be attributed to the coexistence of molecularly dispersedpolymers and aggregates.54

Short poly(phenylene vinylene) chains were grafted onto poly(bis(4-methylphenoxy)-phosphazene) and the copolymer was found to exhibit blue photoluminescence.55

The facile replacement of halide in [N��PCl2]n has been exploited to attach fluorescentcarbazolyl side chains to polyphosphazenes which results in a blue luminescent poly-mer.56 Light emitting diodes were constructed using both of the previous polymers.Carbazole-containing polyphosphazenes have also been studied as potential photo-refractive materials.57 Studies of the gas permeability of mixed substituent polyphos-phazenes have been conducted, and CO2 permeability was found to be particularlysensitive to the proportion of 2-(2-methoxyethoxy)ethoxy-substituents in the phos-phazene backbone.58 Thus, these materials are of potential interest as CO2 selectivemembranes. The effect of silica on the performance of luminescent oxygen sensorscomposed of platinum octaethylporphyrin dyes dispersed in an oxygen permeablematrix of either polydimethylsiloxane or poly(n-butylaminothionylphosphazene) wasinvestigated.59

The synthesis and properties of fascinating phosphorus-containing dendrimers hasbeen reviewed by Majoral and coworkers.60 A novel property of organophosphorusdendrimers is their ability to form gels in water which allow the confinement of avariety of organic and organometallic substances.61 Remarkably, solutions of only1.5–1.8 wt% of polycationic phosphorus dendrimers in water were found to form arigid hydrogel in periods of days to months.

The preparation of poly(cyclodiborazane)s containing disilylene units and theirproperties has been reported.62 GPC analyses of the fluorescent polymers 23 (R =mesityl, 2,4,6-triisopropylphenyl) revealed molecular weights (Mn) of 4,000 and 9,400respectively. Evidence for σ–π conjugation in 23 was provided by UV/vis absorptionstudies and cyclic voltammetry which showed irreversible oxidation and reversiblereduction. A series of poly(cyclodiborazane)s with oligothiophene spacers 24 havealso been synthesised and their light-emitting properties evaluated.63


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4 Polymers containing skeletal d-block elements

The development of methods to successfully incorporate transition metals into thepolymer backbone remains a challenging research frontier. A review of ferrocenepolymers has been published which not only covers linear macromolecules withferrocene in the backbone, but also in the side-chain architecture and dendrimers.64

An article highlighting the now well-established polyferrocenylsilanes has appearedwhich provides an overview of their synthesis, properties, and some exciting possibleapplications.65 An interesting review of transition-metal–polythiophene basedmaterials has appeared.66 Puddephatt has written a nice review of the synthesis andcharacterisation of coordination polymers containing gold() centres.67

An interesting conjugated polymer containing ruthenium in the backbone has beenprepared using the novel method of hydroboration polymerisation.68 The polymeris-ation proceeds by hydroboration of the difunctional di-yne 25 and mesitylborane 26at ambient temperature in THF solution. Reasonable molecular weights were esti-mated for the polymer 27 using GPC analysis (Mn = 1.3 × 104; PDI = 1.8). Evidencefor extended π-conjugation was obtained from UV/vis spectroscopy which showedtwo absorption maxima at 359 and 514 nm.

A fascinating, albeit hypothetical, polymer 28 containing the metal–dinitrogenfunctionality was reported by Floriani and co-workers.69 Although a polymer was notrealised in the present study, the synthesis and X-ray crystal structure of the cumulene29 (L = mesityl) was reported. Band structure calculations for hypothetical polymers28 (L = H) with d2, d3, or d4 metal configurations suggest that conducting propertiesare expected for the neutral d3 polymer.


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Swager and coworkers have reported the formation of thin films of a novel polymercontaining a tungsten-capped calixarane using electropolymerisation.70 Remarkably,oxidation of the polymer backbone results in the formation of highly conductivematerials (σ = 15.5 S cm�1).

A detailed study of the synthesis and properties of novel, conjugated organo-metallic polymers containing coordinated butadiene–cobalt moieties in the mainchain has been reported by Bunz and co-workers.71 The polymers were prepared eitherusing acyclic diyne methathesis (ADIMET) or by the palladium-catalyzed Heck coup-ling reaction. Moderate degrees of polymerisation (n = 20–60) were obtained for thepolymers prepared using the coupling strategy, whereas much longer chain lengthswere obtained using the ADIMET route (n≤230). The morphology and liquid crystal-line properties of the polymers were also investigated. Weder and co-workers reportedthe complexation of poly(p-phenylene ethynylenene)s to platinum() centres resultingin novel organometallic polymers for which photoluminescence is efficientlyquenched.72 In another study, the photoluminescence efficiencies of a series of rigid-rod platinum-containing conjugated polymers were investigated.73

Remarkable one- and two-dimensional blue-purple luminescent coordinationpolymers based on three-coordinate gold() complexes of diphosphines have beenprepared and characterised crystallographically.74 The one-dimensional polymer 30(P–P = trans-Ph2PCH��CHPPh2) can be envisaged as a product of a single ring-opening polymerisation reaction from 31. In another exciting development, uponstanding in solution for 16 weeks, the silver–diphosphine 32 underwent anunprecedented ring-opening polymerisation to yield the novel coordination polymer33.75 Further exciting developments can be anticipated for this unprecedented type ofROP reaction.

A thorough investigation of the relationship between the ring-strain and the poly-merisability of [2]ferrocenophanes has been conducted by Manners and coworkers.76

In particular, [2]ferrocenophanes were prepared which possessed varying degrees ofring strain as indicated by their ring-tilt angles of 11.8(1)� (34a; ERn = SiMe2), 14.9(3)�avg. (34b; ERn = PPh) and 18.2(2)� (34b; ERn = PMes), and 18.5(1)� (34c; ERn = S).


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The [2]carbosilaferrocenophane 34a was resistant towards ROP, presumably due toinsufficient ring strain. In contrast, the [2]carbophosphaferrocenophanes (34b; ERn =PPh or PMes) and the [2]carbothiaferrocenophane 34c each underwent thermallyinduced ROP reactions in the melt to yield high molecular weight polymers 35 and 36respectively. Significantly, the ferrocenophane 34c with a CH2–S bridge could be initi-ated to ROP using cationic initiators MeOTf and BF3�OEt2. This represents the firstcationic ROP of a transition metal-containing heterocycle.

Sheridan, Manners, and coworkers have reported that the mechanism of the transi-tion metal-catalysed ROP of silicon-bridged [1]ferrocenophanes proceeds mainly by aheterogeneous mechanism rather than the homogeneous mechanism which has previ-ously been proposed.77 Oligomerisation studies of 37 with catalyst 38 in the presenceof capping agent Et3SiH revealed, surprisingly, that the dimethylsilyl groups in 38were not incorporated in the polymer 39. Similarly, when [2]platinastannaferro-cenophane was employed as a catalyst for the oligomerisation of fcSiMe2, there wasno evidence for Sn-groups in the polymer. These results, combined with mercuryinhibition studies, suggest that previous homogeneous ROP mechanisms are in-correct, and that colloidal platinum is the main catalyst. This significant discovery isexpected to have implications in other areas of inorganic polymer science since otherheterocycles, such as silacyclobutanes, are well known precursors for metal-catalysedROP.

The formation of cylindrical micelles of controlled length from a poly(ferrocenyl-dimethylsilane-b-dimethylsiloxane) copolymer has been used to create oriented nano-scopic lines on a silicon wafer.78 This clever methodology takes advantage of capillaryforces, acting at the edge of grooves created with an electron beam on a silicon sub-strate coated with a photoresist, to line up the cylindrical micelles along the grooves.After the removal of the resist with acetone and etching with a hydrogen plasma,


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which removes most of the organic components, ceramic wires (length >500 nm;width <10 nm) containing Fe, Si, O and C are left behind in the shape of the initialpattern. The solution self-assembly of poly(ferrocenyldimethylsilane-b-dimethyl-siloxane-b-ferrocenyldimethylsilane), an amphiphilic triblock copolymer, was investi-gated using transmission electron microscopy and atomic force microscopy.79 Interest-ingly, multiple morphologies, such as spheres, cylinders and flower-like aggregateswere observed. In related work, well-defined poly(ferrocenylphenylphosphine-b-isoprene) diblock copolymers (ca. 104 g mol�1; PDI = 1.05 to 1.16) have been preparedusing anionic ROP, and star-like spherical micelles were observed in hexanes.80

Magnetic ceramic microspheres of α-Fe nanoclusters embedded within a siliconcarbide matrix have been obtained from the pyrolysis of self-assembled poly(ferro-cenyldimethylsilane) microspheres.81 In another interesting study, a poly(ferrocenyl-dimethylsilane-b-styrene) block copolymer was used as a lithography mask for thegeneration of a cobalt magnetic dot array.82 The key step involves spin coating theblock copolymer onto the substrate to give a 60 nm thick monolayer of close-packedpolyferrocene microspheres in a polystyrene matrix. The resistance of the polyferro-cene to reactive ion etching in an O2 plasma allows for complete removal of theorganic polymer leaving silicon–iron–oxide microspheres behind.

The synthesis of a poly(ferrocenylgermane) with pendant ferrocenyl groups hasbeen reported,83 as has the ROP of alkoxy-substituted [1]silaferrocenophanes whichyielded novel materials after sol–gel polycondensation.84 A series of interestingaromatic polyethers, thioethers, and amines which are coordinated to a cyclopenta-dienyliron moiety have been prepared and their chemistry investigated.85 A novelcoordination polymer containing ferrocene and bimetallic tetracarboxylate units hasbeen prepared.86 The synthesis of interesting conjugated poly(1,1�-ferrocenylarylenes)with degrees of polymerisation of ca. 9 has been accomplished by the condensation ofLiCp–Ar–CpLi and FeI2.

87

A review of the development of dendrimers based on polypyridine complexes ofruthenium() and omium() has been published.88 In addition, many organometallicdendrimers are discussed in an interesting review article by Astruc and Chardac whichemphasises the use of dendrimers in catalysis.89

References

1 I. Manners, Annu. Rep. Prog. Chem., Sect. A., 1998, 94, 603.2 M. L. Turner, Annu. Rep. Prog. Chem., Sect. A., 1999, 95, 453.3 M. L. Turner, Annu. Rep. Prog. Chem., Sect. A., 2000, 96, 491.4 M. L. Turner, Annu. Rep. Prog. Chem., Sect. A., 2001, 97, 443.5 R. D. Archer, Inorganic and Organometallic Polymers, Wiley-VCH, New York, 2001.6 J. E. Mark, H. R. Allcock and R. West, Inorganic Polymers, Prentice-Hall, Englewood Cliffs, NJ, 1992.7 For a critical review of Archer’s book, see: D. Wöhrle, Angew. Chem., Int. Ed., 2001, 40, 4510.8 Another excellent book which has a chapter on inorganic polymers has recently been published:

U. Schubert, N. Hüsing, Synthesis of Inorganic Materials, Wiley-VCH, Weinheim, 2000.9 I. Manners, Science, 2001, 294, 1664.

10 D. Seyferth, Organometallics, 2001, 20, 4978.11 S. J. Teague, Macromol. Chem. Phys., 2001, 202, 2479.12 F. de Buyl, Int. J. Adhes. Adhes., 2001, 21, 411.13 Y. Kawakami, Macromol. Symp., 2001, 174, 145.14 H. Lang and B. Lühmann, Adv. Mater., 2001, 13, 1523.15 R. Hooper, L. J. Lyons, M. K. Mapes, D. Schumacher, D. A. Moline and R. West, Macromolecules, 2001,

34, 931.


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16 L. V. Interrante, Q. Shen and J. Li, Macromolecules, 2001, 34, 1545.17 W. P. Weber and G. Cai, Macromolecules, 2001, 34, 4355.18 B. P. S. Chauhan, T. E. Ready, Z. Al-Badri and P. Boudjouk, Organometallics, 2001, 20, 2725.19 J. M. Mabry, M. K. Runyon and W. P. Weber, Macromolecules, 2001, 34, 7264.20 M. Barrère, C. Maitre, M. A. Dourges and P. Hémery, Macromolecules, 2001, 34, 7276.21 J. Beckmann and K. Jurkschat, Coord. Chem. Rev., 2001, 215, 267.22 T. Sanji, K. Takase and H. Sakurai, J. Am. Chem. Soc., 2001, 123, 12690.23 H. Nakashima, J. R. Koe, K. Torimitsu and M. Fujiki, J. Am. Chem. Soc., 2001, 123, 4847.24 M. Fujiki, J. R. Koe, M. Motonaga, H. Nakashima, K. Terao and A. Teramoto, J. Am. Chem. Soc., 2001,

123, 6253.25 K. Terao, Y. Terao, A. Teramoto, N. Nakamura, I. Terakawa, T. Sato and M. Fujiki, Macromolecules, 2001,

34, 2682.26 K. Terao, Y. Terao, A. Teramoto, N. Nakamura, M. Fujiki and T. Sato, Macromolecules, 2001, 34, 4519.27 K. Terao, Y. Terao, A. Teramoto, N. Nakamura, M. Fujiki and T. Sato, Macromolecules, 2001, 34, 6519.28 T. Natsume, L. Wu, T. Sato, K. Terao, A. Teramoto and M. Fujiki, Macromolecules, 2001, 34, 7899.29 A. Teramoto, K. Terao, Y. Terao, N. Nakamura, T. Sato and M. Fujiki, J. Am. Chem. Soc., 2001, 123,

12303.30 S. S. Bukalov, L. A. Leites and R. West, Macromolecules, 2001, 34, 6003.31 T. Kanai, H. Ishibashi, Y. Hayashi, K. Oka, T. Dohmaru, T. Ogawa, S. Furukawa and R. West, J. Polym.

Sci., Part B: Polym. Phys., 2001, 39, 1085.32 W. Chunwachirasiri, I. Kanaglekar, M. J. Winokur, J. C. Koe and R. West, Macromolecules, 2001, 34, 6719.33 J. R. Koe, M. Motonaga, M. Fujiki and R. West, Macromolecules, 2001, 34, 706.34 S. Seki, K. Maeda, S. Tagawa, H. Kudoh, M. Sugimoto, Y. Morita and H. Shibata, Adv. Mater., 2001, 13,

1663.35 T. Iseki, M. Narisawa, Y. Katase, K. Oka, T. Dohmaru and K. Okamura, Chem. Mater., 2001, 13, 4163.36 M. Scarlete, N. McCourt, I. S. Butler and J. F. Harrod, Chem. Mater., 2001, 13, 655.37 J. W. Kriesel and T. D. Tilley, Adv. Mater., 2001, 13, 1645.38 Y. Sakurai, D. Yoshimura, H. Ishii, Y. Ouchi, H. Isaka, H. Teramae, N. Matsumoto, S. Hasegawa, N. Ueno

and K. Seki, J. Phys. Chem. B, 2001, 105, 5626.39 S.-Y. Park, L. V. Interrante and B. L. Farmer, Polymer, 2001, 42, 4253.40 S.-Y. Park, L. V. Interrante and B. L. Farmer, Polymer, 2001, 42, 4261.41 T. J. Peckham, P. Nguyen, S. C. Bourke, Q. Wang, D. G. Harrison, P. Zoricak, C. Russell,

L. M. Liable-Sands, A. L. Rheingold, A. J. Lough and I. Manners, Organometallics, 2001, 20, 3035.42 M. Gleria and R. De Jaeger, J. Inorg. Organomet. Polym., 2001, 11, 1.43 K. Inoue and T. Itaya, Bull. Chem. Soc. Jpn., 2001, 74, 1381.44 C. H. Walker, J. V. St. John and P. Wisian-Neilson, J. Am. Chem. Soc., 2001, 123, 3846.45 H. R. Allcock, S. D. Reeves, C. R. de Denus and C. A. Crane, Macromolecules, 2001, 34, 748.46 Y. Chang, S. C. Lee, K. T. Kim, C. Kim, S. D. Reeves and H. R. Allcock, Macromolecules, 2001, 34, 269.47 H. R. Allcock and R. Prange, Macromolecules, 2001, 34, 6858.48 H. R. Allcock, R. Prange and T. J. Hartle, Macromolecules, 2001, 34, 5463.49 H. R. Allcock, C. R. de Denus, R. Prange and W. R. Laredo, Macromolecules, 2001, 34, 2757.50 H. R. Allcock, E. C. Kellam III and M. A. Hofmann, Macromolecules, 2001, 34, 5140; for a highlight of

this work, see: Chem. Eng. News, 2001, July 16, p. 23.51 G. A. Carriedo, J. Jiminez, P. Gómez-Elipe and F. J. García Alonso, Macromol. Rapid Commun., 2001, 22,

444.52 H. R. Allcock, M. A. Hofmann and R. M. Wood, Macromolecules, 2001, 34, 6915.53 G. A. Carriedo, P. Gómez-Elipe, F. J. García Alonso, E. Lizaso, M. E. Muñoz and A. Santamaría,

Macromol. Chem. Phys., 2001, 202, 3437.54 M. T. R. Laguna and M. P. Tarazona, Polymer, 2001, 42, 1751.55 L. M. Leung, C. M. Liu, C. K. Wong and C. F. Kwong, Polymer, 2001, 43, 233.56 Z. Li, J. Qin, X. Deng and Y. Cao, J. Polym. Sci., Part A: Polym. Chem., 2002, 39, 3428.57 Z. Li, J. Li and J. Qin, React. Funct. Polym., 2001, 48, 113.58 C. J. Orme, M. K. Harrup, T. A. Luther, R. P. Lash, K. S. Houston, D. H. Weinkauf and F. F. Stewart,

J. Membr. Sci., 2001, 186, 249.59 X. Lu, I. Manners and M. A. Winnik, Macromolecules, 2001, 34, 1917.60 J.-P. Majoral, A.-M. Caminade, S. Merino, L. Brauge, D. Taton and Y. Gnanou, Macromol. Symp., 2001,

174, 301.61 C. Marmillon, F. Gauffre, T. Gulik-Krzywicki, C. Loup, A.-M. Caminade, J.-P. Majoral, J.-P. Vors and

E. Rump, Angew. Chem., Int. Ed., 2001, 40, 2626.62 N. Matsumi, T. Umeyama and Y. Chujo, Macromolecules, 2001, 34, 3510.63 M. Miyata, N. Matsumi and Y. Chujo, Macromolecules, 2001, 34, 7331.64 R. D. A. Hudson, J. Organomet. Chem., 2001, 637–639, 47.65 K. Kulbaba and I. Manners, Macromol. Rapid Commun., 2001, 22, 711.66 M. O. Wolf, Adv. Mater., 2001, 13, 545.67 R. J. Puddephatt, Coord. Chem. Rev., 2001, 216–217, 313.


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68 N. Matsumi, Y. Chujo, O. Lavastre and P. H. Dixneuf, Organometallics, 2001, 20, 2425.69 E. Solari, J. Hesschenbrouck, R. Scopelliti, C. Floriani and N. Re, Angew. Chem., Int. Ed., 2001, 40, 932.70 A. Vigalok, Z. Zhu and T. M. Swager, J. Am. Chem. Soc., 2001, 123, 7917.71 W. Steffen, B. Köhler, M. Altmann, U. Scherf, K. Stitzer, H.-C. zur Loye and U. H. F. Bunz, Chem. Eur. J.,

2001, 7, 117.72 C. Huber, F. Bangerter, W. R. Caseri and C. Weder, J. Am. Chem. Soc., 2001, 123, 3857.73 J. S. Wilson, N. Chawdhury, M. R. A. Al-Mandhary, M. Younus, M. S. Khan, P. R. Raithby, A. Köhler and

R. H. Friend, J. Am. Chem. Soc., 2001, 123, 9412.74 M.-C. Brandys and R. J. Puddephatt, J. Am. Chem. Soc., 2001, 123, 4839.75 E. Lozano, M. Nieuwenhuyzen and S. L. James, Chem. Eur. J., 2001, 7, 2644.76 R. Resendes, J. M. Nelson, A. Fischer, F. Jäkle, A. Bartole, A. J. Lough and I. Manners, J. Am. Chem. Soc.,

2001, 123, 2116.77 K. Temple, F. Jäkle, J. B. Sheridan and I. Manners, J. Am. Chem. Soc., 2001, 123, 1355.78 J. A. Massey, M. A. Winnik, I. Manners, V. Z.-H. Chan, J. M. Ostermann, R. Enchelmaier, J. P. Spatz and

M. Möller, J. Am. Chem. Soc., 2001, 123, 3147; for a highlight of this work, see: Chem. Eng. News, 2001,April 2, p. 13.

79 R. Resendes, J. A. Massey, K. Temple, L. Cao, K. N. Power-Billard, M. A. Winnik and I. Manners,Chem. Eur. J., 2001, 7, 2414.

80 L. Cao, I. Manners and M. A. Winnik, Macromolecules, 2001, 34, 3353.81 K. Kulbaba, R. Resendes, A. Cheng, A. Bartole, A. Safa-Sefat, N. Coombs, H. D. H. Stöver, J. E. Greedan,

G. A. Ozin and I. Manners, Adv. Mater., 2001, 13, 732.82 J. Y. Cheng, C. A. Ross, V. Z.-H. Chan, E. L. Thomas, R. G. H. Lammertink and G. J. Vancso, Adv. Mater.,

2001, 13, 1174.83 M. Castruita, F. Cervantes-Lee, J. S. Mahmoud, Y. Zhang and K. H. Pannell, J. Organomet. Chem., 2001,

637–639, 664.84 G. Calléja, G. Cerveau and R. J. P. Corriu, J. Organomet. Chem., 2001, 621, 46.85 A. S. Abd-El-Aziz, E. K. Todd and G. Z. Ma, J. Polym. Sci., Part A: Polym. Chem., 2001, 39, 1216.86 W.-M. Xue, F. E. Kühn, E. Herdtweck and Q. Li, Eur. J. Inorg. Chem., 2001, 213.87 G. E. Southard and M. D. Curtis, Organometallics, 2001, 20, 508.88 S. Serroni, S. Campagna, F. Puntoriero, C. Di Pietro, N. D. McClenaghan and F. Loiseau, Chem. Soc. Rev.,

2001, 30, 367.89 D. Astruc and F. Chardac, Chem. Rev., 2001, 101, 2991.


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24??????inorganic and organometallic polymers

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