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Recently, efforts have been made to quantify frailty among older adults with intellectual disability (ID). Medication exposure is associated with frailty among older adults without ID. However, there is little research on this association among older adults with ID. The aim of this study was to examine specifically in people with ID the association between frailty and medication exposure, including anticholinergic and sedative medication exposure.Data were drawn from Wave 2 (2013/2014) of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA), a nationally representative study of older adults with ID in Ireland. A modified version of Fried's frailty phenotype was constructed. Drug burden measures were polypharmacy, Drug Burden Index (DBI), Anticholinergic Cognitive Burden (ACB) and Sedative Load Model. Multinomial logistic regression was used to calculate odds ratios (ORs) and identify associations between frailty and drug burden.This study included 570 participants with ID. Excessive polypharmacy (use of ≥10 medications) was significantly associated with being pre-frail (P = .017; OR = 2.56; 95% confidence interval [CI] 1.19-5.50) and frail (P .001; OR 7.13; 95% CI 2.81-18.12), but DBI, ACB or Sedative Load score were not significantly associated with frailty status (P .05).This is the first study to examine frailty and its association with medication use including anticholinergic and sedative medication burden among older adults with ID. Further research is required to investigate frailty as measured by other frailty models in relation to medication burden in older adults with ID.

Background Discharge and transfer between healthcare facilities put older adults at risk of medication-related problems and early readmission. This review examined the evidence for pharmacist interventions at discharge and patients’ care quality. Methods Eight databases were searched systematically from inception to date, using the appropriate search strategy for each. A search for grey literature was conducted on eight further websites. No filters (e.g. language/dates) were applied. Only prospective randomized/quasi-randomized controlled studies involving patients > 65 years of both genders, discharged alive from hospital, were included. The criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions formed the basis of the assessment, conducted using RevMan 5.3. Results 9738 articles were obtained: 8120 unique articles after duplicate removal. Following screening, 12 studies were identified for inclusion. Interventions comprised follow up, medication review and patient counselling at discharge. Of these, 10 were delivered by pharmacists alone, while the remainder were delivered by pharmacists within a multidisciplinary team. Outcome measures included readmission rates, length of stay, medication adherence and care quality. Nine studies showed significant improvements over standard care, e.g. a decrease in hospital admissions (0.68 OR, p=0.002), improved compliance (P However, three studies did not report positive results: Two reported non-significant improvement but the third reported poorer readmission rates. Risk of bias was low but the high baseline standard of care reduced the scope for improvement in two of these studies. Conclusion The review summarizes pharmacist interventions’ efficacy and their effect on care quality indicators where possible. The majority of interventions at discharge significantly enhanced patients’ care quality. The findings should prove valuable to decision-makers when planning or improving discharge and post-discharge services.

Background This study assessed the pharmacist role in an 80 bed residential care unit by: Quantifying the number and type of pharmacist interventions made and their acceptance rate.Assessing impact of pharmacist interventions on patient care.Assessing staff attitudes towards the clinical pharmacist service. Methods This was a non-blinded, non-comparative evaluation of the existing clinical pharmacist service in the unit. All residents were included. All pharmacist interventions over a 10-week period were recorded, then graded according to the Eadon scale1 by a consultant gerontologist and an experienced pharmacist to assess their impact on patient care. Results There were 615 pharmacist interventions. The most common interventions were: Drug Therapy Review, 34% (n=209) Technical Prescription, 26.5% (n=163) Administration, 15.3% (n=94) Drug Interaction, 10.4% (n=64) Medication Reconciliation, 8.5% (n=52) 98% (n=596) of interventions were rated as having significance to patient care, of which: 48.4% (n=298) and 41.8% (n=257) of the interventions rated as ‘significant and resulting in an improvement in the standard of care’1% (n=6) and 0.5% (n=3) rated as ‘very significant and preventing harm’. There was a statistically significant agreement between the evaluators, κw = 0.231 (95% CI, 0.156 to 0.307), p < .0005. The strength of agreement was fair. Of interventions requiring acceptance by medical team (n=335), 89.9% (n=301) were accepted. 95% (n=36) of staff who responded agreed or strongly agreed that improved patient safety resulted from the pharmacist’s involvement in multidisciplinary medication reviews. Over 92% (n=35) agreed or strongly agreed that their experience of the pharmacist was positive. Conclusion The pharmacist has an important role in our residential care unit. Their involvement in the medicines optimisation process positively impacts patient outcomes and prevents harm. Staff perceived a positive impact of the clinical pharmacist service provided on patient care and patient safety.

Background In Parkinson’s Disease (PD) medication adherence has been neglected. Despite evidence of successful interventions in other chronic diseases, there is currently no review of medication adherence enhancing interventions in PD populations. This review sought to identify and evaluate interventions to improve medication adherence in patients with PD. Methods Six online databases (PubMed, EMBASE, Medline, PsycINFO, CinahlCOMPLETE, AMED) were searched. Key concepts “Medication adherence” and “Parkinson’s disease” were used. Reference lists of retrieved studies were hand searched. Studies were assessed for inclusion against pre-specified eligibility criteria. Data extraction was carried out using a standardised data extraction table. Critical appraisal was undertaken using the JADAD score, CASP Randomised Controlled Trial (RCT) checklist, “Quality Assessment tool for before-after studies with no control group” and the TREND statement checklist. Results The search resulted in 612 records of which five met inclusion criteria (3 RCT, 2 before-after studies). A total of 496 PD patients were included. Interventional strategies investigated were educational intervention, adherence therapy, effect of a Parkinson’s Tracker App (PTA) and intervention by a pharmacist. Five (100%) of the studies included in this review reported a statistically significant improvement in medication adherence post-intervention and some improvements in symptoms. Conclusion This is the first review of medication adherence in the PD population. Several different interventions proved effective in enhancing medication adherence, but the studies were small, short term and the risk of bias ranged from moderate to high. Consequently, the results may not be generalisable to other PD populations.

Background: The National Integrated Care Programme for Older People (NICPOP), formerly NCPOP aims to support older people to live well in their homes by developing primary and secondary care services for older people, especially those with complex needs. The programme develops integrated intermediate care which traverses both hospital and community settings through multidisciplinary and interagency teams. This team-based approach to the integration of health services is a novel innovation in Irish health service delivery and will require, over time, a shift in cultures of care to allow for the development of competencies for inter-professional collaboration across the care continuum. The ECLECTIC project will develop an implementation framework for achieving, maintaining and monitoring competencies for interprofessional collaboration among multi-disciplinary teams charged with delivering care for older people across the continuum from acute to community settings. Design: The ECLECTIC research design has been developed in collaboration with the NICPOP. In phase one of the project, a co-design team will collaborate to define and shape competencies for interprofessional collaboration. Phase two will involve the delivery of a collective leadership intervention over a 10-month period with multidisciplinary professionals working with older people across two geographical regions (Mullingar/Midlands and Beaumont/Dublin North). Each group will comprise of members of two multidisciplinary teams charged with coordinating and delivering care to older people across the continuum of acute to community care. Observations of collaborative inter-professional working will take place before, during, and after intervention. In phase three of the study, analysis of the interview and observation data will be presented to the co-design team in order to develop an implementation framework for future teams. Discussion: The co-design process will develop core competencies and performance indicators for collaborative interprofessional working. The resulting implementation framework will be implemented nationally as part of the NICPOP.

Introduction: Delirium (acute confusion) affects 1 in 8 acute hospital inpatients and is highly distressing for patients and families. It is associated with increased length of hospital stay, risk of falls, mortality and institutionalisation. Early detection improves outcome, whereas established delirium (present for a few days) is difficult to treat. Thus screening for delirium in at-risk patients is key to early detection and treatment to improve outcomes. Description of policy context and objective: NICE guidelines recommend daily delirium screening for high risk patient groups. However, delirium screening and assessment is poorly performed in Irish hospitals (Irish National Audit of Dementia, 2014). We aimed to develop a simple algorithm for delirium screening on hospital wards, helping staff to identify those patients requiring daily delirium screening and outlining the action to be taken when a patient screened positive for delirium. Targeted population: Hospital in-patients on any general medical or surgical ward (i.e. excluding Intensive Care Unit or orthopaedic/neurosurgery wards), with ward nurses performing the daily delirium screening and hospital doctors acting on the abnormal result. Highlights: (innovation, Impact and outcomes) The interdisciplinary national algorithm development team firstly developed an evidence-based algorithm. Two versions were developed- one using the 4AT test (a well-recognised short delirium screening test) and the other using a quicker, deconstructed form. Both versions were piloted in three hospital sites, in a single ward at each site, with extensive user evaluation of the algorithm. Further modification was performed, followed by a second pilot in a single hospital on four wards. The version using the regular 4AT was preferred by users. Staff required pre-use training particularly on how to score patient refusals and using the tool in a patient with severe dementia. A Frequently Asked Questions guide, and an online training tool were developed, to support staff use of the algorithm, based on the pilot studies. This algorithm is being rolled out nationally in 2017 so impact and outcomes can’t be assessed as yet. Comments on transferability: The delirium algorithm was developed for use in all acute hospitals in Ireland. It is highly transferrable to other countries. Conclusions: Any new policy or guideline requires extensive user engagement at all stages of development. Different hospitals have different resources and training needs. Extensive piloting of our proposed algorithm identified areas that required targeted training. This allowed resources to be developed to facilitate adoption of the national policy, targeted to specific end-users needs.

The reaction of trimethylaluminum with the hexameric tert-butylalumoxane, [(tBu)Al(μ3-O)]6, has been investigated. Reaction of [(tBu)Al(μ3-O)]6 with 1 equiv of AlMe3 results in the formation of two isomers (A and B) of the hybrid tert-butylmethylalumoxane, [Al7(μ3-O)6(tBu)6Me3]. The structures of compounds A and B, as determined by NMR spectroscopy and mass spectrometry, consist of [Al6(μ3-O)6(tBu)5Me] alumoxane cages, formed via tert-butyl/methyl exchange, in which one of the edges of the Al6O6 cage is complexed to the (tBu)AlMe2 formed during alkyl exchange. The difference between the isomers results from the geometric relationship of the cage Al-Me group and the opened edge. The activity of [Al7(μ3-O)6(tBu)6Me3], for the [Me2C(Cp)(Flu)]ZrBz2-catalyzed polymerization of 1,5-hexadiene, is significantly increased in comparison to [(tBu)Al(μ3-O)]6. The effect of additional equivalents of AlMe3 on the cocatalytic activity of [Al7(μ3-O)6(tBu)6Me3] suggests that a maximum activity is obtained at a [(tBu)Al(μ3...

Reaction of M(tBu)3 (M = Al, Ga) with neol-H2 (2,2-dimethylpropane-1,3-diol) yields [M2(tBu)4(neol-H)2], M = Al (1) and Ga (2), respectively. Use of an equimolar mixture of Al(tBu)3 and Ga(tBu)3 allows for the formation of [AlGa(tBu)4(neol-H)2] (3). Compounds 1 and 2 may be considered as bifunctional (two OH groups), tetradentate (4O) ligands as highlighted by their reactivity with Group 13 hydrides and alkyls. Reaction of compound 1 with AlH3(NMe3), AlH2Cl(NMe3) and AlMe3 yields the tri-aluminium compounds, [Al3(tBu)4(X)(neol)2] with X = H (4), X = Cl (5), Me (6), respectively. Similarly, compound 2 reacts with Ga(tBu)3 to yield the tri-gallium compound, [Ga3(tBu)5(neol)2] (7). The mixed metal complexes, [Ga2Al(tBu)4(X)(neol)2], where X = H (8), Me (9) and tBu (10), are formed by the reaction of compound 2 with AlH3(NMe3), AlMe3, and Al(tBu)3, respectively. The solid state conformation of the neol backbone and the 1H NMR chemical shift of the neol's CH2 protons, in compounds 4–10, are both dependent on the steric bulk of the substituent of the central metal. Thermolysis of compound 2 in toluene results in the formation of [Ga3(tBu)4(CH2Ph)(neol)2] (11), while the reaction of 2 with LiOH in Et2O and hexane yields [Ga3Li4(tBu)6(neol)3(OH)(THF)] (12) and [Ga2Li(tBu)4(OH)2(neol-H)] (13), respectively. The molecular structures of compounds 1, 2, 4–13 and [Ga3Cl5(OSiMe2OSiMe2O)2] (14) have been determined by X-ray crystallography.

The reaction of Al(tBu)3 with ethylene glycol (HOCH2CH2OH) in hexane yields “alucone” polymers, [Al(tBu)2x(OCH2CH2O)1.5-x]n (0.3 ≤ 2x ≤ 0.8), with the concurrent formation of [Al2(tBu)3(OCH2CH2O)(OCH2CH2OH)] (1). If the reaction is carried out in Et2O solution, then [Al3(tBu)5(OCH2CH2O)2] (2) may be isolated. The molecular structure of compound 1 consists of a dimer formed by the alkoxide termini of two ligands bridging the Al(tBu) and Al(tBu)2 units. The Al(tBu) moiety is chelated by the nonbridging oxygens of the glycolate ligands, one of which remains protonated. Compound 2 consists of two Al(tBu)2 units and two glycolate ligands forming a cryptand-like 10-membered heterocycle; the Al(tBu) unit is positioned capping the four oxygen atoms. As with the previously reported ethoxy-substituted alucone polymers, [Al(OR)2x(OCH2CH2O)1.5-x]n, thermolysis of [Al(tBu)2x(OCH2CH2O)1.5-x]n, results in the formation of η-alumina (η-Al2O3) as determined by XRD. This is in contrast to the formation of γ-Al2O3 from the ...

Dialkylaluminium compounds with bi-functional ligands, [E(CH2)xNR2]– (x = 2, 3; E = S, NR′) have been prepared, and compared to those that contain [O(CH2)xNR2]–, in order to investigate the effect of the anionic termini on the structure of the aluminium compounds, [R2Al{E(CH2)xNR′2}]n. The reaction of R2NCH2CH2SH·HCl with Li[Al(tBu)3Me], formed in situ from Al(tBu)3 with MeLi, yields (tBu)2Al(SCH2CH2NR2), R = Me 1 and Et 2. Reaction of Al(tBu)3 with HN(Me)CH2CH2NMe2 and HN(Me)CH2CH2CH2NMe2 ultimately yields (tBu)2Al[N(Me)CH2CH2NMe2] 3 and (tBu)2Al[N(Me)CH2CH2CH2NMe2] 4, respectively. Reaction of HAl(iBu)2 with HN(Me)CH2CH2NMe2 yields [(iBu)2Al{µ-N(Me)CH2CH2NMe2}]2 5, while [H2Al{µ-N(R)CH2CH2NMe2}]2, R = Me 6 and Et 7, are formed from the reaction of AlH3(NMe3) with HN(R)CH2CH2NMe2. The molecular structures of compounds 1, 2, 6 and 7 have been determined by X-ray crystallography. Compounds 1–4 are monomeric with five (1–3) and six (4) membered chelate heterocyclic rings. Compound 5 exists as a monomer/dimer equilibrium in solution, in contrast, compounds 6 and 7 exist as bridged dimers. The formation of monomeric chelate structures for compounds 1 and 2, rather than the bridged dimers found for the alkoxide analogs is due to the relative ligand base strength. However, the formation of monomers in the case of compounds 3 and 4 is found to be due to a combination of the steric bulk of the aluminium alkyl and the geometry at the potentially bridging amide group. These results demonstrate a remote geometric control over the degree of association.

Reaction of Al(tBu)3 with (tBu)3Al[O(H)CH2CH2CH2NMe2] yielded the Lewis acid–base complex [(tBu)2Al{µ-OCH2CH2CH2N(Me)2Al(tBu)3}]2 1. Compound 1 is also formed directly when 2 equivalents of Al(tBu)3 reacts with 1 equivalent of [(tBu)2Al(µ-OCH2CH2CH2NMe2)]2. In contrast, the reaction of 2 equivalents of Al(tBu)3 with 1 equivalent of [Me2Al(µ-OCH2CH2NMe2)]2 yielded Me2Al(µ-OCH2CH2NMe2)Al(tBu)3 2. The molecular structure of compound 2 shows the AlMe2 moiety chelate bound to the anionic bidentate ligand, while the Al(tBu)3 unit is bonded to the anionic terminus of the ligand. The formation of compound 1 is proposed to occur via the tert-butyl analog of compound 2, i.e., (tBu)2Al(µ-OCH2CH2CH2NMe2)Al(tBu)3, which is unstable due to significant tBu· · ·tBu inter-ligand interactions. The implications of the differences in products is discussed with respect to the extent of intra-molecular Al· · ·N coordination in compounds of the general formula [R2Al{µ-O(CH2)nNMe2}]2.

The molecular structure of (tBu)3Al[O=C(OPh)2] has been determined. The increase in the C=O bond distance [1.258(4) A] when compared to free O=C(OPh)2 [1.191(3) A], is presented in respect to the activating ability of aluminum Lewis acids. Crystal data: monoclinic, P21/n, a = 10.653(2), b = 18.486(4), c = 14.551(3) A, β = 108.07(3)°, and V = 2724.3(9) A3 for Z = 4.

Reaction of [(tBu)2Ga(μ-Cl)]2 with Li(o-C6H4NMe2) yields [ ( t Bu ) 2 Ga (o- C 6 H 4 NMe 2 )] 2 (1). The atmospheric oxidation/hydrolysis of 1 results in the isolation of ( t Bu ) 2 Ga (o- C 6 H 4 Me 2 ] (2). The structure of compound 2 (as determined by X-ray crystallography) consists of a gallium dimer in which one of the ortho-(dimethylamino)phenyl ligands is oxidized and the other exhibits strong intramolecular O3·N hydrogen bonding ( ΔG ‡ = 57.3 kJ mol −1 ) to the hydroxide bridge. A pathway for the formation of 2 is proposed. Reaction of compound 1 with OPPh3 results in the formation of the Lewis acid-base complex [ ( t Bu ) 2 Ga (o- C 6 H 4 NMe 2 )(OPPh3) (3), whose structure has been confirmed by X-ray crystallography.

Two new polytopic ligands L1 and L2 have been synthesized. They consist of a central tren unit to which three 1,4,7,10-tetraazacyclododecane rings are attached via an ethylene and a trimethylene bridge, respectively. The complexation properties of L1 and L2 towards Cu(2+) and Ni(2+) were studied by potentiometric pH titration, UV-Vis, EPR spectroscopy and kinetic techniques. As a comparison, the Cu(2+) and Ni(2+) complexes with L3 (1-(N-methyl-2-aminoethyl-1,4,7,10-tetraazacyclododecane)) were also investigated. The crystal structures of [CuL3H(H(2)O)](ClO(4))(3) and [NiL3Cl](ClO(4)) were solved and show that the side chain in its protonated form is not involved in coordination, whereas deprotonated it binds to the metal ion. The thermodynamically stable 3:1 complexes of L1 or L2 have a metal ion in the three macrocyclic units. However, when three equivalents of Cu(2+) are added to L1 or L2 the metal ion first binds to the tren unit and only then to the macrocycles. The kinetics of the different steps of complexation have been studied and a mechanism is proposed.

The crystal and molecular structure of (tBu)3AlP(nPr)3 has been determined. The Al(1)−P(1) bond distance [2.594(3) A] is slightly longer than other aluminum-phosphine complexes; however, the geometry about aluminum is similar to that of the [AlCl(tBu)3]− anion, suggesting that the geometry about the aluminum in tri-tert-butylaluminum complexes is defined by the size of thetert-butyl ligands and not as a consequence of the steric bulk of the Lewis base. Crystal data: Monoclinic,P2t,a=8.932(2),b=16.832(3),c=9.328(2), A, β=114.36(3)°,V=1277.6(6) A3,Z=4,R.=0.055,R w =0.053.

Reaction of [(iBu)2AlH]2 with l-ephedrine yields [(iBu)2Al{μ-OC(H)(Ph)CH(Me)N(H)Me}]2 (1). Reaction of Al(tBu)3 with (2S,3R)-(+)-4-(dimethylamino)-1,2-diphenyl-3-methyl-2-butanol (ChiraldR) yields (tBu)2Al[OC(CH2Ph)(Ph)CH(Me)CH2NMe2] (2). The molecular structures of compounds 1 and 2 have been determined by X-ray crystallography. Compound 2 is monomeric with a six membered chelate heterocyclic ring. In contrast, compound 1 exists as a bridged dimer. The formation of monomeric chelate species for compound 2, rather than the alkoxide bridged dimer as is found for 1 is found to be due to the steric bulk of the aluminum alkyl and substitution at the ligand's α-carbon. Crystal data: (1) orthorhombic, P212121, a = 10.987(2), b = 18.795(4), c = 19.270(4) A, V = 3979(1) A3, Z = 4, R = 0.1056, R w = 0.2454. (2) tetragonal, I4, a = 22.236(3), c = 10.784(1) A, V = 5332.0(5) A3, Z = 8, R = 0.0485, R w = 0.0537.

To develop an understanding of the factors that control the strength of the Lewis acid−base interactions in five-coordinate compounds of aluminum, dimeric dialkylaluminum compounds [R2Al{μ-O(CH2)nER‘x}]2 (n = 2, 3; ER‘x = OR‘, SR‘, NR‘2) have been prepared from AlR3 and the appropriate substituted alcohol, thiol, or amine: [R2Al(μ-OCH2CH2OMe)]2, R = tBu (1), iBu (2), and Et (3); [R2Al(μ-OCH2CH2OnBu)]2, R = tBu (4) and Me (5); [R2Al(μ-OCH2CH2CH2OMe)]2, R = tBu (6) and Me (7); (tBu)2Al(μ-OnBu)(μ-OCH2CH2OMe)Al(tBu)2 (11); [R2Al(μ-OCH2CH2SMe)]2, R = tBu (12), iBu (13), Et (14), and Me (15); [R2Al(μ-OCH2CH2CH2SMe)]2, R = tBu (16) and Me (17); [R2Al(μ-OCH2CH2NMe2)]2, R = tBu (18), iBu (19), Et (20), and H (21); [(tBu)2Al(μ-OCH2CH2NH2)]2 (22); [(tBu)2Al(μ-OCH2CH2CH2NH2)]2 (23). The molecular structures of compounds 1, 2, 6, 7, 12, 13, 16, 18−22, and [Me2Al(μ-OCH2CH2NMe2)]2 have been determined by X-ray crystallography. The solution structures have been probed by 13C NMR spectroscopy using the alkoxide derivativ...

The interaction of R2AlH with cyclic siloxanes leads to rupture of the silicon−oxygen framework and yields aluminum polysiloxides. The room-temperature reaction of R2AlH with (Me2SiO)3 yields the a...

Reaction of Al(Bu t ) 3 with between 1 and 2 equivalents of HOCH 2 CH 2 CH 2 NMe 2 allows for the isolation of the Lewis acid–base complex, (Bu t ) 3 Al[O(H)CH 2 CH 2 CH 2 NMe 2 ] 1, which undergoes alkane elimination above 45 °C to yield [(Bu t ) 2 Al(µ-OCH 2 CH 2 CH 2 NMe 2 )] 2 2. Compound 2 is also formed directly when 2 equivalents of Al(Bu t ) 3 react with 1 equivalent of HOCH 2 CH 2 CH 2 NMe 2 . The molecular structure of 1 shows an Al–O bond distance comparable to that found in the bridging alkoxide compounds 2 and [(Bu t ) 2 Al(µ-OPr n )] 2 3, suggesting that the Al–O · · · H unit may be considered analogous to a bridging alkoxide unit, Al(µ-OR)Al, as a consequence of a significant contribution from the zwitterionic alkoxide - /ammonium + form made possible by a strong intraligand hydrogen bond. The kinetics of the conversion of 1 into 2 have been studied. A large activation energy and positive deuterium isotope effect are consistent with breaking of the hydrogen bond during the transition state. The reaction of (Bu t ) 3 Al(NMe 3 ) 4 with ethanol yields [(Bu t ) 2 Al(µ-OEt)] 2 5. The reaction of Al(Bu t ) 3 with HN(Me)(CH 2 ) n NMe 2 (n = 3 or 2) yields the stable Lewis acid–base adducts (Bu t ) 3 Al[NH(Me)CH 2 CH 2 CH 2 NMe 2 ] 6 and (Bu t ) 3 Al[NH(Me)CH 2 CH 2 NMe 2 ] 7, respectively. The molecular structures of compounds 1–3, 6 and 7 have been confirmed by X-ray crystallography. The implications of the structures and stabilities of compounds 1, 6 and 7 are discussed with respect to the protonolysis reaction of aluminium alkyls with Bronsted acids (HX) and a new intermolecular elimination mechanism is proposed.

The preferential hydrolytic cleavage of an A1-N versus an A1-C bond allows for isolation of the base stabilized alkylalumoxane,[(tBu)2A1{NH(Me)CH2CH2NMe2}]2(µ-O), from the hydrolysisof the intra-molecularly stabilized amino-amide compound, (tBu)2A1[N(Me)CH2CH2NMe2], providing a possible general route to alkylalumoxanes.

Two novel symmetric polytopic ligands L(1) and L(2) have been synthesized. They are composed of three 1,4,8,11-tetraazacyclotetradecane macrocycles which are connected to a central tren moiety via an ethylene and a trimethylene bridge, respectively. The complexation potential and the speciation diagrams of L(1) and L(2) towards Cu(2+) and Ni(2+) were determined by spectrophotometric and potentiometric titrations. Insight into the geometry of the Cu(2+) complexes is provided by UV-VIS and EPR spectroscopy. The simplified ligands L(3) and L(4) are utilized as references for an aminoethyl- and a tren-substituted tetraaza macrocycle to help assign the EPR spectra of the polytopic ligands L(1) and L(2). At a metal-to-ligand ratio of 3 : 1, the metal cations are preferentially bound to the tetraaza macrocycles of L(1) and L(2) in a square planar geometry. At high pH values, a nitrogen atom of the tren moiety in L(1) serves as an additional ligand in an axial position leading to a square pyramidal coordination around Cu(2+), whereas in L(2) no such geometry change is observed. At a metal-to-ligand ratio of 4 : 1, the additional metal cation resides in the central tren moiety of L(1) and L(2). However, in contrast to the typical trigonal bipyramidal geometry found in the [Cutren](2+) complex, the fourth Cu(2+) has a square pyramidal coordination caused by the interaction with the Cu(2+) cations in the macrocycles (as evidenced by EPR spectra). Since the sequence of metal complexation is such that the first three metal ions always bind to the three macrocycles of L(1) and L(2) and the fourth to the tren unit, it is possible to prepare heteronuclear complexes such as [Cu(3)NiL](8+) or [Ni(3)CuL](8+), which can be unambiguously identified by their spectral properties.