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[EN] The cationic complex [(JohnPhos-Au)(3)(acetylide)][SbF6] (JohnPhos=(2-biphenyl)di-tert-butylphosphine, L1) has been characterised structurally and features an acetylide-trigold(I)-JohnPhos system; the trinuclear-acetylide unit, coordinated to the monodentate bulk phosphines, adopts an unprecedented mu,eta(1),eta(2),eta(1)coordination mode with an additional interaction between distal phenyl rings and gold centres. Other cationic sigma,pi-[(gold(I)L1)(2)] complexes have also been isolated. The reaction of trimethylsilylacetylene with various alcohols (iPrOH,nBuOH,n-HexOH) catalysed by cationic [Au(I)L1][SbF6] complexes in CH(2)Cl(2)at 50 degrees C led to the formation of acetaldehyde acetals with a high degree of chemo- and regioselectivity. The reaction mechanism was studied, and several organic and inorganic intermediates have been characterised. A comparative study with the analogous cationic [Cu(I)L1][PF6] complex revealed different behaviour; the copper metal is lost from the coordination sphere leading to the formation of cationic vinylphosphonium and copper nanoparticles. Additionally, a new catalytic approach for the formation of this high-value cationic vinylphosphonium has been established., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and RTI2018-89027-CO2-R1) and the Generalitat Valenciana (Prometeo 2013-2014) is gratefully acknowledged.

A novel family of dipropargylamines has been synthesised in one pot through a double catalytic A-coupling of five components. Cationic [Au-L][SbF] complexes (L=JohnPhos) are extremely active catalysts for the double A-coupling of primary amines (aliphatic or aromatic), formaldehyde and trimethylsilylacetylene. Several reactions of LAu-amine complexes with organic reagents were studied and followed by NMR and HRMS (ESI) analyses, providing information about the reaction mechanism. Specifically, the role of the π-gold(I) acetylide complexes as active catalyst species was firmly confirmed. Most of the intermediates of this five-component coupling were identified by GC-MS spectrometry, lending support to the mechanistic proposal. In some cases, cationic amine-gold(I)-L complexes corresponding to the activated reagent or intermediate were isolated and characterised by single-crystal X-ray diffraction analysis, their spectroscopic properties were recorded, and their catalytic activity evaluated. Protic solvents influence the course of the reaction by effecting the double deprotection of dipropargylamines, providing a convenient route to dipropargylamines with double-deprotected silyl moieties. When NaOH is present in the reaction media, formation of cationic acetylide-dipropargylamine gold(I) and neutral hydroxide LAuOH complexes, respectively, as high and less active intermediate catalyst forms occur., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2015‐69153‐CO2‐R1) and Generalidad Valenciana (Prometeo 2013‐014) is gratefully acknowledged.

[EN] The design of new hybrid materials with tailored properties at the nano-, meso-, and macro-scale, with the use of structural functional nanobuilding units, is carried out to obtain specific multi-functional materials. Organization into controlled 1D, 2D, and 3D architectures with selected functionalities is key for developing advanced catalysts, but this is hardly accomplished using conventional synthesis procedures. The use of pre-formed nanostructures, derived either from known materials or made with specific innovative synthetic methodologies, has enormous potential in the generation of multi-site catalytic materials for one-pot processes. The present concept article introduces a new archetype wherein self-assembled nanostructured builder units are the base for the design of multifunctional catalysts, which combine catalytic efficiency with fast reactant and product diffusion. The article addresses a new generation of versatile hybrid organic-inorganic multi-site catalytic materials for their use in the production of (chiral) high-added-value products within the scope of chemicals and fine chemicals production. The use of those multi-reactive solids for more nanotechnological applications, such as sensors, due to the inclusion of electron donor-acceptor structural arrays is also considered, together with the adsorption-desorption capacities due to the combination of hydrophobic and hydrophilic sub-domains. The innovative structured hybrid materials for multipurpose processes here considered, can allow the development of multi-stage one-pot reactions with industrial applications, using the materials as one nanoreactor systems, favoring more sustainable production pathways with economic, environmental and energetic advantages., The authors are grateful for financial support from the Spanish Government by MAT2014-52085-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683. The European Union is also acknowledged by ERC-AdG-2014-671093-SynCatMatch.

[EN] The Pt-catalyzed hydrosilylation of alkynes is the procedure of choice to obtain vinylsilanes, and is claimed to be the most relevant application of Pt in organic synthesis. More than half a century after its discovery, only b-vinylsilanes (anti-Markovnikov addition) are obtained with simple Pt catalysts, whereas a-vinylsilanes (Markovnikov addition)remain elusive compounds.Here the catalysis of the Markovnikov hydrosilylation of terminal alkynes by Pt3clusters, in parts-per-million amounts, to give a wide variety of a-vinylsi-lanes in reasonable isolated yields and with turnover fre-quencies that can reach up to one million per hour is reported. Moreover, these a-vinylsilanes are reactive in well-stablished C@Cbond-forming cascade reactions, in which thecorresponding b-isomers are unreactive. Besides its efficiency and synthetic usefulness, this catalytic system is an excellent example of how the atom-by-atomaggregation of a catalytic metal leads to a different selectivity for a given reaction, Financial support by MINECO (RETOS program, CTQ201455178-R) and "Severo Ochoa" program is acknowledged. M. A. R.-C. thanks for a FPU scholarship.

Photobiocatalysts are constituted by a semiconductor with or without a light harvester that activates an enzyme. A logical source of inspiration for the development of photobiocatalysts has been natural photosynthetic centers. In photobiocatalysis, the coupling of the semiconductor and the enzyme frequently requires a natural cofactor and a relay transferring charge carriers from the semiconductor. The most widely studied photobiocatalysts so far make use of conduction band electrons of excited semiconductors to promote enzymatic reductions mediated by NAD(+)/NADH and an electron relay. The present review presents the state of the art in the field and has been organized based on the semiconductor and the reaction type including oxidations, hydrogen generation, and CO2 reduction. The possibility of direct enzyme activation by the semiconductor and the influence of the nature of mediator are also discussed as well as the use of mimics of the enzyme active center in combination with the semiconductor. The final section summarizes the state of the art of photobiocatalysis and comments on our view on future developments of the field., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2012-32315) is gratefully acknowledged. J.A.M.-A. acknowledges the assistance of the CSIC for the award of a Postdoctoral JAE-Doc contract co-financed by the European Social Fund.

A highly isolated monoatomic gold catalyst, with single gold atoms dispersed on multiwalled carbon nanotubes (MWCNTs), has been synthesized, characterized, and tested in heterogeneous hydrogenation of 1,3-butadiene and 1-butyne with parahydrogen to maximize the polarization level and the contribution of the pairwise hydrogen addition route. The Au/MWCNTs catalyst was found to be active and efficient in pairwise hydrogen addition and the estimated contributions from the pairwise hydrogen addition route are at least an order of magnitude higher than those for supported metal nanoparticle catalysts. Therefore, the use of the highly isolated monoatomic catalysts is very promising for production of hyperpolarized fluids that can be used for the significant enhancement of NMR signals. A mechanism of 1,3-butadiene hydrogenation with parahydrogen over the highly isolated monoatomic Au/MWCNTs catalyst is also proposed.

[EN] Cationic Cu L complexes (L=Buchwald-type phosphane) with N co-ligands have been characterised by structural and spectroscopic properties. These copper(I) complexes are extremely active catalysts, far more active than analogous gold(I) complexes, to promote the single and double A3 coupling of terminal alkynes, pyrrolidine and formaldehyde. The activity data show the possible ways in which the solvent can influence the catalytic performance by limiting complex solubility, by solvent decomposition or instability of the copper(I) redox state. Isolation of copper(I) complexes that are likely to be the key catalytic species has allowed light to be shed on the reaction mechanism, Financial support by the Spanish ministry of Economy and Competitiveness (Severo Ochoa and CTQ2012-32315) and Generalidad Valenciana (Prometeo 2012-014) is gratefully acknowledged. We also thank Dr. J. A. Vidal-Moya (ITQ) for assistance and discussions on EPR and NMR analysis.

The triflimide iron(III) salt [Fe(NTf2)3] promotes the direct hydration of terminal and internal alkynes with very good Markovnikov regioselectivities and high yields. The enhanced carbophilic Lewis acidity of the FeIII cation mediated by the weakly-coordinating triflimide anion is crucial for the catalytic activity. The iron(III) metal salt can be recycled in the form of the OPPh3/[Fe(NTf2)3] system with similar activity and selectivity. However, spectroscopic and kinetic studies show that [Fe(NTf2)3] hydrolyzes under the reaction conditions and that catalytically less active Brønsted species are formed, which points to a Lewis/Brønsted co-catalysis. This triflimide-based catalytic system is regioselective for the hydration of internal aryl-alkynes and opens the door to a new synthetic route to alkyl ketophenones. As a proof of concept, the synthesis of two antipsychotics Haloperidol and Melperone, with general butyrophenone-like structure, is shown., The work has been supported by Consolider-Ingenio 2010 (proyecto MULTICAT), and PROMETEO from Generalitat Valenciana. J.R.C.A. thanks MCIINN for a pre-doctoral FPU fellowship. A. L. P. thanks ITQ for financial support. We thank Dr. J. A. Vidal-Moya for the EPR measurements.

A family of hybrid mesoporous materials with high temperature stability was obtained by the suitable covalent combination of two types of siloxane precursors. Specifically, cubic T8 polyhedral oligomeric (POSS) and aryl bridged silsesquioxane monomers (1,4-bis(triethoxysilyl)benzene, BTEB) play the role of nanobuilders. An optimal molar ratio of the two precursors (5¿25 mol% of total silicon content from the BTEB disilane) generated a homogenous, highly accessible, and well-defined mesoporous material with hexagonal symmetry and narrow pore size distribution. Physicochemical, textural, and spectroscopic analysis corroborated the effective integration and preservation of the two different nanoprecursors, thereby confirming the framework of the mesoporous hybrid materials. A post-synthesis amination treatment allowed the effective incorporation of amino groups onto the aryl linkers, thereby obtaining a stable and recyclable basic catalyst for use in C C bond-formation processes., The authors thank the Spanish MICINN (Consolider Ingenio 2010-MUL-TICAT (CSD2009-00050) and MAT2011-29020-C02-01) for their financial support. T. G. thanks the CSIC for the award of a JAE pre-doctoral fellowship.

Copper(II) oxide nanoparticles supported on magnesia have been prepared from CuII supported on magnesia by hydrogen reduction at 400°C followed by storage under ambient conditions. X-ray photoelectron spectroscopy of the material clearly shows that immediately after the reduction copper(0)-metal nanoparticles are present on the magnesia support, but they undergo fast oxidation to copper oxide upon contact with the ambient for a short time. TEM images show that the catalytically active CuO/MgO material is formed of well-dispersed copper oxide nanoparticles supported on fibrous MgO. CuO/MgO exhibits a remarkable catalytic activity for the monoborylation of aromatic, aliphatic, terminal, and internal alkynes, the products being formed with high regio- (borylation at the less substituted carbon) and stereoselectivity (trans-configured). CuO/MgO exhibits complete chemoselectivity towards the monoborylation of alkynes in the presence of alkenes. Other metal nanoparticles such as gold or palladium are inactive towards borylation, but undergo undesirable oligomerization or partial hydrogenation of the C[TRIPLE BOND]C triple bond. In contrast, platinum, either supported on magnesia or on nanoparticulate ceria, efficiently promotes the stereoselective diborylation of alkynes to yield a cis-configured diboronate alkene. By using platinum as the catalyst we have developed a tandem diborylation/hydrogenation reaction that gives vic-diboronated alkanes from alkynes in one pot., Financial support from the Spanish Ministry of Science and Innovation (Consolider Ingenio 2010 project MULTICAT and CQT2009-11853) is gratefully acknowledged. A.G. thanks the CSIC for a research associate JAE contract. We also thank Fundacion Areces for the financial support of this research.

The copper and gold metal-organic frameworks (MOFs) [Cu(3)(BTC)(2)(H(2)O)(3)](n), [Cu(3)(BTC)(2)] (BTC=benzene-1,3,5-tricarboxylate), and IRMOF-3-SI-Au are active and reusable solid catalysts for the cyclopropanation of alkenes with high chemo- and diastereoselectivities. This type of material gives better results than previous solid catalysts while working together with the homogeneous catalysts. These MOFs can help to bridge the gap between homogeneous and heterogeneous catalysis.

The Zr-containing metal-organic frameworks (MOFs) formed by terephthalate (UiO-66) and 2-aminoterephthalate ligands [UiO-66(NH(2))] are two notably water-resistant MOFs that exhibit photocatalytic activity for hydrogen generation in methanol or water/methanol upon irradiation at wavelength longer than 300 nm. The apparent quantum yield for H(2) generation using monochromatic light at 370 nm in water/methanol 3:1 was of 3.5% for UiO-66(NH(2)). Laser-flash photolysis has allowed detecting for UiO-66 and UiO-66(NH(2)) the photochemical generation of a long lived charge separated state whose decay is not complete 300 μs after the laser flash. Our finding and particularly the influence of the amino group producing a bathochromic shift in the optical spectrum without altering the photochemistry shows promises for the development of more efficient MOFs for water splitting.

Substituted 1,5-benzodiazepines are selectively synthesized in one pot from substituted nitroaromatics and ketones. The reaction is performed in the presence of hydrogen and in the absence of solvent by using a bifunctional solid catalyst with a chemoselective hydrogenation functional group capable of reducing the nitro group to a diamino group and an acid functional group, which catalyzes the cyclocondensation of the amino group with the ketone.

Several heterometallic nitrido complexes were prepared by reaction of the imido-nitrido titanium complex [{Ti(eta(5)-C(5)Me(5))(mu-NH)}(3)(mu(3)-N)] (1) with amido derivatives of Group 13-15 elements. Treatment of 1 with bis(trimethylsilyl)amido [M{N(SiMe(3))(2)}(3)] derivatives of aluminum, gallium, or indium in toluene at 150-190 degrees C affords the single-cube amidoaluminum complex [{(Me(3)Si)(2)N}Al{(mu(3)-N)(2)(mu(3)-NH)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}] (2) or the corner-shared double-cube compounds [M(mu(3)-N)(3)(mu(3)-NH)(3){Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}(2)] [M = Ga (3), In (4)]. Complexes 3 and 4 were also obtained by treatment of 1 with the trialkyl derivatives [M(CH(2)SiMe(3))(3)] (M = Ga, In) at high temperatures. The analogous reaction of 1 with [{Ga(NMe(2))(3)}(2)] at 110 degrees C leads to [{Ga(mu(3)-N)(2)(mu(3)-NH)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}(2)] (5), in which two [GaTi(3)N(4)] cube-type moieties are linked through a gallium-gallium bond. Complex 1 reacts with one equivalent of germanium, tin, or lead bis(trimethylsilyl)amido derivatives [M{N(SiMe(3))(2)}(2)] in toluene at room temperature to give cube-type complexes [M{(mu(3)-N)(2)(mu(3)-NH)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}] [M = Ge (6), Sn (7), Pb (8)]. Monitoring the reaction of 1 with [Sn{N(SiMe(3))(2)}(2)] and [Sn(C(5)H(5))(2)] by NMR spectroscopy allows the identification of intermediates [RSn{(mu(3)-N)(mu(3)-NH)(2)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}] [R = N(SiMe(3))(2) (9), C(5)H(5) (10)] in the formation of 7. Addition of one equivalent of the metalloligand 1 to a solution of lead derivative 8 or the treatment of 1 with a half equivalent of [Pb{N(SiMe(3))(2)}(2)] afford the corner-shared double-cube compound [Pb(mu(3)-N)(2)(mu(3)-NH)(4){Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}(2)] (11). Analogous antimony and bismuth derivatives [M(mu(3)-N)(3)(mu(3)-NH)(3){Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)}(2)] [M = Sb (12), Bi (13)] were obtained through the reaction of 1 with the tris(dimethylamido) reagents [M(NMe(2))(3)]. Treatment of 1 with [AlCl(2){N(SiMe(3))(2)}(OEt(2))] affords the precipitation of the singular aluminum-titanium square-pyramidal aggregate [{{(Me(3)Si)(2)N}Cl(3)Al(2)}(mu(3)-N)(mu(3)-NH)(2){Ti(3)(eta(5)-C(5)Me(5))(3)(mu-Cl)(mu(3)-N)}] (14). The X-ray crystal structures of 5, 11, 13, 14, and [AlCl{N(SiMe(3))(2)}(2)] were determined.

2,4,6-Triphenylpyrylium (TP(+)) forms host-guest complexes with cucurbiturils (CBs) in acidic aqueous solutions. (1)H NMR spectroscopic data indicates that complexation takes place by encapsulation of the phenyl ring at the four position within CB. Formation of the complex with CB[6] and CB[7] leads to minor shifts in the fluorescence wavelength maximum (lambda(fl)) or quantum yield (Phi(fl)). In sharp contrast, for complexes with CB[8], the emission results in the simultaneous observation of fluorescence (lambda(fl)=480 nm, Phi(fl)=0.05) and room-temperature phosphorescence (lambda(ph)=590 nm, Phi(ph)=0.15). The occurrence of room-temperature phosphorescence can be used to detect the presence of CB[8] visually in solution. Molecular modeling and MM2 molecular mechanics calculations suggest that this effect arises from locking the conformational mobility of the 2- and 6-phenyl rings as a result of CB[8] encapsulation. The remarkably high room-temperature phosphorescence quantum yield of the TP(+)@CB[8] complex has been advantageously applied to develop an electroluminescent cell that contains this host-guest complex. In contrast, analogous cells prepared with TP(+) or TP(+)@CB[7] fail to exhibit electroluminescence.

The addition of iron to high-area TiO2 (Degussa P25, a mixture of anatase and rutile) increases the number of oxygen defect sites that react with O2 to form peroxide and superoxide species. In the presence of gold nanoclusters on the TiO2 surface, the superoxide species become highly reactive, and the activity of the supported gold catalyst for CO oxidation is approximately twice that of the most active comparable catalysts described in the literature. Images of the catalyst obtained by scanning transmission electron microscopy combined with spectra of the catalyst measured in the working state (Raman, extended X-ray absorption fine structure, and X-ray absorption near-edge structure) indicate strong interactions of gold with the support and the presence of iron near the interfaces between the gold clusters and the TiO2 support. The high activity of the catalysts is attributed to the presence of defects in these sites that activate oxygen.

The molecular mechanism of the Baeyer-Villiger oxidation of cyclohexanone with hydrogen peroxide catalyzed by the Sn-beta zeolite has been investigated by combining molecular mechanics, quantum-chemical calculations, spectroscopic, and kinetic techniques. A theoretical study of the location of Sn in zeolite beta was performed by using atomistic force-field techniques to simulate the local environment of the active site. An interatomic potential for Sn/Si zeolites, which allows the simulation of zeolites containing Sn in a tetrahedral environment, has been developed by fitting it to the experimental properties of quartz and SnO 2 (rutile). The tin active site has been modeled by means of a Sn(OSiH 3 ) 3 OH cluster, which includes a defect in the framework that provides the flexibility necessary for the interaction between the adsorbates and the Lewis acid center. Two possible reaction pathways have been considered in the computational study, one of them involving the activation of the cyclohexanone carbonyl group by Sn (1) and the other one involving hydrogen peroxide being activated through the formation of a tin-hydroperoxo intermediate (2). Both the quantum-chemical results and the kinetic study indicate that the reaction follows mechanism 1, and that the catalyst active site consists of two centers: the Lewis acid Sn atom to which cyclohexanone has to coordinate, and the oxygen atom of the Sn-OH group that interacts with H 2 O 2 forming a hydrogen bond.

Treatment of [[Ti(eta(5)-C(5)Me(5))(micro-NH)](3)(micro(3)-N)] (1) with the imido complexes [Ti(NAr)Cl(2)(py)(3)] (Ar=2,4,6-C(6)H(2)Me(3)) and [Ti(NtBu)Cl(2)(py)(3)] in toluene affords the single azatitanocubanes [[Cl(2)(ArN)Ti]( micro(3)-NH)(3)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]].(C(7)H(8)) (2.C(7)H(8)) and [[Cl(2)Ti](micro(3)-N)(2)(micro(3)-NH)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]] (3), respectively. Similar reactions of complex 1 with the niobium and tantalum imido derivatives [[M(NtBu)(NHtBu)Cl(2)(NH(2)tBu)](2)] (M=Nb, Ta) in toluene give the single azaheterometallocubanes [[Cl(2)(tBuN)M](micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]] (M=Nb (4), Ta (5)), both complexes react with 2,4,6-trimethylaniline to yield the analogous species [[Cl(2)(ArN)M](micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]].(C(7)H(8)) (Ar=2,4,6-C(6)H(2)Me(3), M=Nb (6.C(7)H(8)), Ta (7.C(7)H(8))). Also the azaheterodicubanes [M[micro(3)-N)(2)(micro(3)-NH)](2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)](2)].2C(7)H(8) [M=Ti (8.2C(7)H(8)), Zr (9.2C(7)H(8))], and [M[(micro(3)-N)(5)(micro(3)-NH)][Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)](2)].2 C(7)H(8) (Nb (10.2C(7)H(8)), Ta (11.2C(7)H(8))) were prepared from 1 and the homoleptic dimethylamido complex [M(NMe(2))(x)] (x=4, M=Ti, Zr; x=5, M=Nb, Ta) in toluene at 150 degrees C. X-ray crystal structure determinations were performed for 6 and 10, which revealed a cube- and double-cube-type core, respectively. For complexes 2 and 4-7 we observed and studied by DNMR a rotation or trigonal-twist of the organometallic ligands [[Ti(eta(5)-C(5)Me(5))(micro-NH)](3)(micro(3)-N)] (1) and [(micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]](1-). Density functional theory calculations were carried out on model complexes of 2, 3, and 8 to establish and understand their structures.

The photochemical treatment of μ 3 -alkylidyne complexes [{TiCp * (μ-O)] 3 (μ 3 -CR)] (R = H (1), Me (2), Cp * = η 5 -C 5 Me 5 ) with the amines (2,6-Me 2 C 6 H 3 )NH 2 , Et 2 NH, and Ph 2 NH and the imine Ph 2 C=NH leads to the partial hydrogenation of the alkylidyne moiety that is supported on the organometallic oxide, [Ti 3 Cp * 3 O 3 ], and the formation of new oxoderivatives [{TiCp * (μ-O)} 3 -(μ-CHR)(R'NR"] (R"= 2,6-Me 2 C 6 H 3 , R' = H, R=H (3), Me (4); R'=R"= Et, R = H (5), Me (6); R' = R" = Ph, R=H (7), Me (8)) and [{TiCp * (μ-O)} 3 (μ-CHR)(N=CPh 2 )] (R = H (9). R = Me (10)), respectively. A sequential transfer hydrogenation process occurs when complex 1 is treated with tBuNH 2 , which initially gives the μ-methylene [{TiCp * (μ-O)} 3 (μ-CH 2 )(HNtBu)] (11) complex and finally, the alkyl derivative [{TiCp * (μ-O)} 3 (μ--NtBu)Me] (12). Furthermore, irradiation of solutions of the μ 3 -alkylidyne complexes 1 or 2 in the presence of diamines o-C 6 H 4 (NH 2 ) 2 and H 2 NCH 2 CH 2 NH 2 (en) affords [{TiCp * (μ-O)} 3 (μ 3 -η 2 -NC 6 H 4 NH)] (13) and [{TiCp * (μ-O)} 3 (μ 3 -η 2 -NC 2 H 4 NH)] (14) by either methane or ethane elimination, respectively. In the reaction of 1 with en, an intermediate complex [{TiCp * (μ-O)} 3 (μ-CH 2 )(NH-CH 2 CH 2 NH 2 )] (15) is detected by 'H NMR spectroscopy. Thermal treatment of the complexes 4-10 quantitatively regenerates the starting μ 3 -alkylidyne compounds and the amine R' 2 NH or the imine Ph 2 C=NH; however, heating of solutions of 3 or 4 in [D 6 ]benzene or a equimolecular mixture of both at 170°C produces methane, ethane, or both, and the complex [{TiCp * -(μ-O)} 3 {μ 3 -η 2 -NC 6 H 3 (Me)CH 2 }] (16). The molecular structure of 8 has been established by single-crystal X-ray analysis.