Leadership styles of Teaching Managers and their Influence on Teaching Performance and Metacognitive Processes

El presente artículo se enmarca en la investigación de los estilos de liderazgo y su influencia en el desempeño profesional de las instituciones de educación públicas cuya exploración se centró en un grupo de rectores, que permitieron identificar de forma voluntaria sus estilos de liderazgo y éstos cómo inciden en su rol al interior de la comunidad educativa desde los procesos metacognitivos. La metodología implementada para este estudio fue de corte descriptivo, con un enfoque cualitativo desde el paradigma fenomenológico interpretativo; para el trabajo de campo se diseñó y aplicó una entrevista semiestructurada. Como resultados, se evidenció que las capacidades intelectuales, de formación, de principios y los procesos metacognitivos, son fundamentales en cargos gerenciales que demandan integridad y responsabilidad, planeación, resolución de conflictos, toma de decisiones, construcción de escenarios de convivencia, aprendizaje y trabajo en equipo y se encuentran presentes y estrechamente relacionados en quienes se reconocen como líderes carismáticos, siendo el estilo de liderazgo interpersonal predominante en los rectores participantes, en busca de resultados de calidad para sus instituciones educativas.This article is framed in the investigation of leadership styles and their influence on the professional performance of public education institutions whose exploration focused on a group of principals, who allowed them to voluntarily identify their leadership styles and how they affect in its role within the educational community from metacognitive processes. The methodology implemented for this study was descriptive, with a qualitative approach from the interpretive phenomenological paradigm; For field work, a semi-structured interview was designed and applied. As results, it was evident that intellectual abilities, training, principles and metacognitive processes are fundamental in managerial positions that demand integrity and responsibility, planning, conflict resolution, decision making, construction of coexistence, learning and work scenarios. as a team and are present and closely related in those who are recognized as charismatic leaders, being the predominant interpersonal leadership style in the participating principals, in search of quality results for their educational institutions

Durabilité du post-traitement des moteurs diesel : modèle prédictif de l'impact du vieillissement hydrothermique et de l'empoisonnement sur les performances du DOC et de la SCR

La réduction des contaminants issus de la combustion des carburants est l'un des objectifs les plus importants des années à venir, leurs limites étant abaissées à chaque mise à jour des législations. Ils sont réduits par des catalyseurs de post-traitement ; cependant, les systèmes catalytiques réduisent leurs performances avec une utilisation continue. L'utilisation d'outils de simulation facilite la conception des systèmes de dépollution, mais les modèles cinétiques permettant de prédire la désactivation font défaut dans la littérature. Deux des catalyseurs de post-traitement des véhicules lourds ont été étudiés dans leur état frais et désactivés, les catalyseurs d'oxydation diesel (DOC) et la réduction catalytique sélective (SCR). La désactivation a été réalisée par vieillissement hydrothermal (HTA) et empoisonnement du biodiesel (Ca, Mg, K, Na et P). Ensuite, un modèle cinétique global a été développé pour prédire leur activité catalytique dans leurs états frais et désactivés. Plusieurs catalyseurs DOC constitués de Pt-Pd/Al2O3 ont été synthétisés en variant leur teneur en métaux précieux. Le changement de composition du DOC frais a pu être reproduit par le modèle en supposant une énergie d'activation constante pour toutes les réactions. Le vieillissement hydrothermal a pu être reproduit en diminuant le facteur pré-exponentiel. Pour l'empoisonnement du biodiesel, la forte désactivation a modifié le mécanisme de réaction, et a pu être reproduite en changeant l'énergie d'activation de l'oxydation du NO. La combinaison de tous les poisons a été reproduite en supposant que P était la seule espèce. L'activité SCR dépendait fortement de la distribution entre les sites actifs où le NH3 était adsorbé. Une équation générale pour reproduire l'effet de l'HTA sur toutes les réactions a été développée, qui pourrait être extrapolée pour différentes températures et temps d'exposition. Elle a permis de prédire toutes les réactions, y compris l'inhibition par le C3H6. L'étude des catalyseurs commercial actuellement utilisés par différentes entreprises automobiles a montré comment les différents types de catalyseurs interagissent entre eux pour maximiser la réduction des contaminants. Le modèle global a été appliqué à ces catalyseurs mais seuls ceux dont la composition était la plus proche ont pu être correctement reproduitsThe reduction of contaminants from fuel combustion is one of the most important objectives of the following years, with their limits lowering in each update of the legislations. They are reduced by after-treatment catalysts; however, the catalytic systems reduce their performance with continued use. Then, the use of simulation tools facilitates the design of the depollution systems, yet kinetic models that can predict the deactivation are missing from literature. Two of the after-treatment catalysts of heavy-duty vehicles were studied in their fresh and deactivated states, the diesel oxidation catalysts (DOC) and selective catalytic reduction (SCR). The deactivation was performed by hydrothermal ageing (HTA) and biodiesel poisoning (Ca, Mg, K, Na and P). Afterwards, a global kinetic model was developed for predicting their catalytic activity in their fresh and deactivated states. Several DOC catalysts consisting on Pt-Pd/Al2O3 were synthetized varying its content of precious metals. The change in composition for the fresh DOC could be reproduced by the model by assuming constant activation energy for all reactions. Hydrothermal ageing could be reproduced by lowering the pre-exponential factor. For biodiesel poisoning the strong deactivation modified the reaction mechanism, and could be reproduced by changing the activation energy of NO oxidation. The combination of all poisons was replicated by assuming P as the only specie. The SCR activity was strongly dependent on the distribution between actives where NH3 was adsorbed. A general equation for reproducing the effect of HTA on all the reactions was developed, that could be extrapolated for different temperatures and exposure times. It was able of predicting all the reactions including the inhibition by C3H6. The study of state-of-the-art catalysts currently used by different automotive companies showed how the different types of catalysts interact with each other for maximizing the reduction of contaminants. The global model was applied to these catalysts but only the ones with the closer composition could be correctly reproduce

Preparation of Diazoalkane Complexes of Ruthenium and Their Cyclization Reactions with Alkenes and Alkynes

The diazoalkane complexes [Ru(η5 -C5H5)- (N2CAr1Ar2)(PPh3)(L)]BPh4 (1−5: Ar1 = Ar2 = Ph (a), Ar1 = Ph and Ar2 = p-tolyl (b), Ar1Ar2 = C12H8 (c), Ar1 = Ph and Ar2 = PhCO (d); L = PPh3 (1), P(OMe)3 (2), P(OEt)3 (3), PPh(OEt)2 (4), But NC (5)) were prepared by allowing the chloro compounds RuCl(η5 -C5H5)(PPh3)(L) to react with the diazoalkanes Ar1Ar2CN2 in ethanol. Treatment of complexes 1−5 with ethylene (CH2CH2) under mild conditions (1 atm, room temperature) led not only to the η2 -ethylene complexes [Ru(η5 -C5H5)(η2 -CH2CH2)(PPh3)(L)]BPh4 (10−14) but also to dipolar (3 + 2) cycloaddition, affording the 4,5-dihydro-3H-pyrazole derivatives [Ru(η5 -C5H5){η1 -N NC(Ar1Ar2)CH2CH2}(PPh3)(L)]BPh4 (6−9). Acrylonitrile (CH2C(H)CN) reacted with diazoalkane complexes 2 and 3 to give the 1H-pyrazoline derivatives [Ru(η5 -C5H5){η1 -NC(CN)CH2C(Ar1Ar2)NH}(PPh3)(L)]BPh4 (19, 20). However, reactions with propylene (CH2C(H)CH3), maleic anhydride (ma, CHCHCO(O)CO) and dimethyl maleate (dmm, CH3OCOCHCHOCOCH3) led to the η2 -alkene complexes [Ru(η5 -C5H5)(η2 -R1CHCHR2)(PPh3)(L)]BPh4 (17−22). Treatment of the diazoalkane complexes 1 and 2 with acetylene CHCH under mild conditions (1 atm, room temperature) led to dipolar cycloaddition, affording the 3H-pyrazole complexes [Ru(η5 -C5H5){η1 -NNC(Ar1Ar2)CHCH}(PPh3) {P(OMe)3}]BPh4 (24), whereas reactions with the terminal alkynes PhCCH and But CCH gave the vinylidene derivatives [Ru(η5 -C5H5){CC(H)R}(PPh3){P(OMe)3}]BPh4 (25, 26). The alkyl propiolates HCCCOOR1 (R1 = Me, Et) also reacted with complexes 2 to give the 3H-pyrazole complexes [Ru(η5 -C5H5){η1 -NNC(Ar1Ar2)C(COOR1)CH}(PPh3)- {P(OMe)3}]BPh4 (27, 28). The complexes were characterized by spectroscopy and by X-ray crystal structure determinations of [Ru(η5 -C5H5){η1 -NC(CN)CH2C(Ph)(p-tolyl)NH}(PPh3){P(OMe)3}]BPh4 (19b), [Ru(η5 -C5H5){η2 -CHCHCO(O)CO}- (PPh3){P(OMe)3}]BPh4 (21), and [Ru(η5 -C5H5){η1 -NNC(C12H8)CHCH}(PPh3){P(OMe)3}]BPh4 (24c)

Hydrolysis of Coordinated Diazoalkanes To Yield Side-On 1,2-Diazene Derivatives

Diazoalkane complexes [Ru­(η⁵-C₅Me₅)­(N₂CAr1Ar2)­(PPh₃)­{P­(OR)₃}]­BPh₄ [R = Me (<b>1</b>), Et (<b>2</b>); Ar1 = Ar2 = Ph (<b>a</b>); Ar1 = Ph, Ar2 = <i>p</i>-tolyl (<b>b</b>); Ar1Ar2 = C₁₂H₈ (<b>c</b>)] were prepared by allowing chloro complexes RuCl­(η⁵-C₅Me₅)­(PPh₃)­[P­(OR)₃] to react with diazoalkane Ar1Ar2CN₂ in ethanol. The treatment of compounds <b>1</b> and <b>2</b> with H₂O afforded 1,2-diazene derivatives [Ru­(η⁵-C₅Me₅)­(η²-NHNH)­(PPh₃)­{P­(OR)₃}]­BPh₄ (<b>3</b> and <b>4</b>) and ketone Ar1Ar2CO. A reaction path involving nucleophilic attack by H₂O on the coordinated diazoalkane is proposed. The complexes were characterized spectroscopically (IR and NMR) and by X-ray crystal structure determination of [Ru­(η⁵-C₅Me₅)­(η²-NHNH)­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>3</b>)

Preparation and Reactivity of Stannyl Complexes of Ruthenium(II) Stabilized by an Indenyl Ligand

Trichlorostannyl complexes Ru­(SnCl₃)­(η⁵-C₉H₇)­(PPh₃)­L (<b>1</b>; L = P­(OMe)₃, P­(OEt)₃) were prepared by allowing chloro compounds RuCl­(η⁵-C₉H₇)­(PPh₃)­L to react with SnCl₂·2H₂O in ethanol. Treatment of compounds <b>1</b> with NaBH₄ in ethanol yielded the tin trihydride derivatives Ru­(SnH₃)­(η⁵-C₉H₇)­(PPh₃)­L (<b>2</b>). The reaction of trichlorostannyl complexes <b>1</b> with MgBrMe in diethyl ether afforded the chlorodimethylstannyl derivatives Ru­(SnClMe₂)­(η⁵-C₉H₇)­(PPh₃)­L (<b>3</b>), whereas reaction with Li⁺CCPh^– in THF yielded the trialkynylstannyl compounds Ru­[Sn­(CCPh)₃]­(η⁵-C₉H₇)­(PPh₃)­L (<b>4</b>). Treatment of the trihydridostannyl complexes <b>2</b> with the alkyl propiolate HCCCOOR led to the trivinylstannyl derivatives Ru­[Sn­{C­(COOR)CH₂}₃]­(η⁵-C₉H₇)­(PPh₃)­L (<b>5</b>,<b> 6</b>; R = Me, Et). However, the reaction of [Ru]–SnH₃ (<b>2</b>) with the propargylic alcohol HCCCPh₂OH yielded the alkene H₂CC­(H)­CPh₂OH and the hydride RuH­(η⁵-C₉H₇)­(PPh₃)­L (<b>7</b>). Treatment of tin trihydride complexes <b>2</b> with H₂O led to the trihydroxostannyl derivatives Ru­[Sn­(OH)₃]­(η⁵-C₉H₇)­(PPh₃)­L (<b>8</b>). Protonation of [Ru]–SnH₃ (<b>2</b>) with triflic acid (HOTf) produced the very unstable dihydridostannyl compound Ru­[SnH₂(OTf)]­(η⁵-C₉H₇)­(PPh₃)­L (<b>9</b>). Stabilization of SnH₂ species was achieved by protonation with HOTf at −30 °C of the cyclopentadienyl compound Ru­(SnH₃)­(η⁵-C₅H₅)­(PPh₃)­[P­(OMe)₃], which yielded the complex Ru­[SnH₂(OTf)]­(η⁵-C₅H₅)­(PPh₃)­[P­(OMe)₃] (<b>10a</b>). The complexes were characterized by spectroscopy (IR and ¹H, ³¹P, ¹³C, and ¹¹⁹Sn NMR data) and by X-ray crystal structure determinations of Ru­[Sn­(CCPh)₃]­(η⁵-C₉H₇)­(PPh₃)­[P­(OEt)₃] (<b>4b</b>) and Ru­[Sn­(OH)₃]­(η⁵-C₉H₇)­(PPh₃)­[P­(OEt)₃] (<b>8b</b>)

Preparation of Diazoalkane Complexes of Ruthenium and Their Cyclization Reactions with Alkenes and Alkynes

The diazoalkane complexes [Ru­(η⁵-C₅H₅)­(N₂CAr1Ar2)­(PPh₃)­(L)]­BPh₄ (<b>1</b>–<b>5</b>: Ar1 = Ar2 = Ph (<b>a</b>), Ar1 = Ph and Ar2 = <i>p-</i>tolyl (<b>b</b>), Ar1Ar2 = C₁₂H₈ (<b>c</b>), Ar1 = Ph and Ar2 = PhCO (<b>d</b>); L = PPh₃ (<b>1</b>), P­(OMe)₃ (<b>2</b>), P­(OEt)₃ (<b>3</b>), PPh­(OEt)₂ (<b>4</b>), Bu^<i>t</i>NC (<b>5</b>)) were prepared by allowing the chloro compounds RuCl­(η⁵-C₅H₅)­(PPh₃)­(L) to react with the diazoalkanes Ar1Ar2CN₂ in ethanol. Treatment of complexes <b>1</b>–<b>5</b> with ethylene (CH₂CH₂) under mild conditions (1 atm, room temperature) led not only to the η²-ethylene complexes [Ru­(η⁵-C₅H₅)­(η²-CH₂CH₂)­(PPh₃)­(L)]­BPh₄ (<b>10</b>–<b>14</b>) but also to dipolar (3 + 2) cycloaddition, affording the 4,5-dihydro-3<i>H</i>-pyrazole derivatives [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­CH₂CH₂}­(PPh₃)­(L)]­BPh₄ (<b>6</b>–<b>9</b>). Acrylonitrile (CH₂C­(H)­CN) reacted with diazoalkane complexes <b>2</b> and <b>3</b> to give the 1<i>H</i>-pyrazoline derivatives [Ru­(η⁵-C₅H₅)­{η¹-NC­(CN)­CH₂C­(Ar1Ar2)NH}­(PPh₃)­(L)]­BPh₄ (<b>19</b>, <b>20</b>). However, reactions with propylene (CH₂C­(H)­CH₃), maleic anhydride (ma, CHCHCO­(O)CO) and dimethyl maleate (dmm, CH₃OCOCHCHOCOCH₃) led to the η²-alkene complexes [Ru­(η⁵-C₅H₅)­(η²-R1CHCHR2)­(PPh₃)­(L)]­BPh₄ (<b>17</b>–<b>22</b>). Treatment of the diazoalkane complexes <b>1</b> and <b>2</b> with acetylene CHCH under mild conditions (1 atm, room temperature) led to dipolar cycloaddition, affording the 3<i>H</i>-pyrazole complexes [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­CHCH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>24</b>), whereas reactions with the terminal alkynes PhCCH and Bu^<i>t</i>CCH gave the vinylidene derivatives [Ru­(η⁵-C₅H₅)­{CC­(H)­R}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>25</b>,<b> 26</b>). The alkyl propiolates HCCCOOR1 (R1 = Me, Et) also reacted with complexes <b>2</b> to give the 3<i>H</i>-pyrazole complexes [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­C­(COOR1)CH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>27</b>,<b> 28</b>). The complexes were characterized by spectroscopy and by X-ray crystal structure determinations of [Ru­(η⁵-C₅H₅)­{η¹-NC­(CN)­CH₂C­(Ph)­(<i>p</i>-tolyl)NH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>19b</b>), [Ru­(η⁵-C₅H₅)­{η²-CHCHCO­(O)CO}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>21</b>), and [Ru­(η⁵-C₅H₅)­{η¹-NNC­(C₁₂H₈)­CHCH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>24c</b>)

Azo Complexes of Osmium(II): Preparation and Reactivity of Organic Azide and Hydrazine Derivatives

Mixed-ligand hydride complexes OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) [L = P­(OMe)₃, P­(OEt)₃] were prepared by allowing OsHCl­(CO)­(PPh₃)₃ (<b>1</b>) to react with an excess of phosphite P­(OR)₃ in refluxing toluene. Dichloro compounds OsCl₂(CO)­(PPh₃)₂L (<b>3</b>,<b> 4</b>) were also prepared by reacting <b>1</b>, <b>2</b> with HCl. Treatment of hydrides OsHCl­(CO)­(PPh₃)₂L (<b>2</b>), first with triflic acid and then with an excess of RN₃ afforded organic azide complexes [OsCl­(η¹-N₃R)­(CO)­(PPh₃)₂L]­BPh₄ (<b>5</b>–<b>7</b>) [R = 4-CH₃C₆H₄CH₂, C₆H₅CH₂, C₆H₅; L = P­(OEt)₃]. Benzylazide complexes react in CH₂Cl₂/ethanol solution, leading to the imine derivative [OsCl­(CO)­{η¹-NHC­(H)­C₆H₄-4-CH₃}­(PPh₃)₂{P­(OEt)₃}]­BPh₄ (<b>8b</b>). Hydrazine complexes [OsCl­(CO)­(RNHNH₂)­(PPh₃)₂L]­BPh₄ (<b>9</b>–<b>11</b>) [R = H, CH₃, C₆H₅; L = P­(OMe)₃, P­(OEt)₃] were prepared by allowing hydride species OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) to react first with triflic acid and then with an excess of hydrazine. Aryldiazene derivatives [OsCl­(CO)­(ArNNH)­(PPh₃)₂L]­BPh₄ (<b>12</b>,<b> 13</b>) were also prepared following two different methods: (i) by oxidizing arylhydrazine [OsCl­(C₆H₅NHNH₂)­(CO)­(PPh₃)₂L]­BPh₄ (<b>11</b>) with Pb­(OAc)₄ in CH₂Cl₂ at −30 °C; (ii) by allowing hydride species OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) to react with aryldiazonium cations ArN₂⁺ (Ar = C₆H₅, 4-CH₃C₆H₄) in CH₂Cl₂. The complexes were characterized spectroscopically and by X-ray crystal structure determination of OsHCl­(CO)­(PPh₃)₂[P­(OEt)₃] (<b>2b</b>) and [OsCl­{η¹-NHC­(H)­C₆H₄-4-CH₃}­(CO)­(PPh₃)₂{P­(OEt)₃}]­BPh₄ (<b>8b</b>)

Cycloaddition of Coordinated Diazoalkanes to Ethene To Yield 3<i>H</i>‑Pyrazole Derivatives

Diazoalkane complexes [Ru­(η⁵-C₅H₅)­(N₂CAr1Ar2)­(PPh₃)­L]­BPh₄ (<b>1</b>,<b> 2</b>; Ar1 = Ph, Ar2 = <i>p-</i>tolyl; Ar1Ar2 = C₁₂H₈; L = P­(OMe)₃, P­(OEt)₃) were prepared by allowing compounds RuCl­(η⁵-C₅H₅)­(PPh₃)­L to react with diazoalkane in ethanol. Treatment of complexes <b>1</b> and <b>2</b> with ethylene under mild conditions (1 atm, room temperature) led not only to the ethylene complexes [Ru­(η⁵-C₅H₅)­(η²-CH₂CH₂)­(PPh₃)­L]­BPh₄ (<b>5</b>,<b> 6</b>) but also to dipolar (3 + 2) cycloaddition, affording the 3<i>H</i>-pyrazole derivatives [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­CH₂CH₂}­(PPh₃)­L]­BPh₄ (<b>3</b>,<b> 4</b>). The propylene complexes [Ru­(η⁵-C₅H₅)­(η²-CH₃CHCH₂)­(PPh₃)­L]­BPh₄ (<b>7</b>,<b> 8</b>) were also prepared. The compounds were characterized by spectroscopy and by X-ray crystal structure determinations of <b>2a</b>, <b>3b</b>, and <b>7</b>

Azo Complexes of Osmium(II): Preparation and Reactivity of Organic Azide and Hydrazine Derivatives

Mixed-ligand hydride complexes OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) [L = P­(OMe)₃, P­(OEt)₃] were prepared by allowing OsHCl­(CO)­(PPh₃)₃ (<b>1</b>) to react with an excess of phosphite P­(OR)₃ in refluxing toluene. Dichloro compounds OsCl₂(CO)­(PPh₃)₂L (<b>3</b>,<b> 4</b>) were also prepared by reacting <b>1</b>, <b>2</b> with HCl. Treatment of hydrides OsHCl­(CO)­(PPh₃)₂L (<b>2</b>), first with triflic acid and then with an excess of RN₃ afforded organic azide complexes [OsCl­(η¹-N₃R)­(CO)­(PPh₃)₂L]­BPh₄ (<b>5</b>–<b>7</b>) [R = 4-CH₃C₆H₄CH₂, C₆H₅CH₂, C₆H₅; L = P­(OEt)₃]. Benzylazide complexes react in CH₂Cl₂/ethanol solution, leading to the imine derivative [OsCl­(CO)­{η¹-NHC­(H)­C₆H₄-4-CH₃}­(PPh₃)₂{P­(OEt)₃}]­BPh₄ (<b>8b</b>). Hydrazine complexes [OsCl­(CO)­(RNHNH₂)­(PPh₃)₂L]­BPh₄ (<b>9</b>–<b>11</b>) [R = H, CH₃, C₆H₅; L = P­(OMe)₃, P­(OEt)₃] were prepared by allowing hydride species OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) to react first with triflic acid and then with an excess of hydrazine. Aryldiazene derivatives [OsCl­(CO)­(ArNNH)­(PPh₃)₂L]­BPh₄ (<b>12</b>,<b> 13</b>) were also prepared following two different methods: (i) by oxidizing arylhydrazine [OsCl­(C₆H₅NHNH₂)­(CO)­(PPh₃)₂L]­BPh₄ (<b>11</b>) with Pb­(OAc)₄ in CH₂Cl₂ at −30 °C; (ii) by allowing hydride species OsHCl­(CO)­(PPh₃)₂L (<b>2</b>) to react with aryldiazonium cations ArN₂⁺ (Ar = C₆H₅, 4-CH₃C₆H₄) in CH₂Cl₂. The complexes were characterized spectroscopically and by X-ray crystal structure determination of OsHCl­(CO)­(PPh₃)₂[P­(OEt)₃] (<b>2b</b>) and [OsCl­{η¹-NHC­(H)­C₆H₄-4-CH₃}­(CO)­(PPh₃)₂{P­(OEt)₃}]­BPh₄ (<b>8b</b>)

Preparation of Diazoalkane Complexes of Ruthenium and Their Cyclization Reactions with Alkenes and Alkynes

The diazoalkane complexes [Ru­(η⁵-C₅H₅)­(N₂CAr1Ar2)­(PPh₃)­(L)]­BPh₄ (<b>1</b>–<b>5</b>: Ar1 = Ar2 = Ph (<b>a</b>), Ar1 = Ph and Ar2 = <i>p-</i>tolyl (<b>b</b>), Ar1Ar2 = C₁₂H₈ (<b>c</b>), Ar1 = Ph and Ar2 = PhCO (<b>d</b>); L = PPh₃ (<b>1</b>), P­(OMe)₃ (<b>2</b>), P­(OEt)₃ (<b>3</b>), PPh­(OEt)₂ (<b>4</b>), Bu^<i>t</i>NC (<b>5</b>)) were prepared by allowing the chloro compounds RuCl­(η⁵-C₅H₅)­(PPh₃)­(L) to react with the diazoalkanes Ar1Ar2CN₂ in ethanol. Treatment of complexes <b>1</b>–<b>5</b> with ethylene (CH₂CH₂) under mild conditions (1 atm, room temperature) led not only to the η²-ethylene complexes [Ru­(η⁵-C₅H₅)­(η²-CH₂CH₂)­(PPh₃)­(L)]­BPh₄ (<b>10</b>–<b>14</b>) but also to dipolar (3 + 2) cycloaddition, affording the 4,5-dihydro-3<i>H</i>-pyrazole derivatives [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­CH₂CH₂}­(PPh₃)­(L)]­BPh₄ (<b>6</b>–<b>9</b>). Acrylonitrile (CH₂C­(H)­CN) reacted with diazoalkane complexes <b>2</b> and <b>3</b> to give the 1<i>H</i>-pyrazoline derivatives [Ru­(η⁵-C₅H₅)­{η¹-NC­(CN)­CH₂C­(Ar1Ar2)NH}­(PPh₃)­(L)]­BPh₄ (<b>19</b>, <b>20</b>). However, reactions with propylene (CH₂C­(H)­CH₃), maleic anhydride (ma, CHCHCO­(O)CO) and dimethyl maleate (dmm, CH₃OCOCHCHOCOCH₃) led to the η²-alkene complexes [Ru­(η⁵-C₅H₅)­(η²-R1CHCHR2)­(PPh₃)­(L)]­BPh₄ (<b>17</b>–<b>22</b>). Treatment of the diazoalkane complexes <b>1</b> and <b>2</b> with acetylene CHCH under mild conditions (1 atm, room temperature) led to dipolar cycloaddition, affording the 3<i>H</i>-pyrazole complexes [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­CHCH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>24</b>), whereas reactions with the terminal alkynes PhCCH and Bu^<i>t</i>CCH gave the vinylidene derivatives [Ru­(η⁵-C₅H₅)­{CC­(H)­R}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>25</b>,<b> 26</b>). The alkyl propiolates HCCCOOR1 (R1 = Me, Et) also reacted with complexes <b>2</b> to give the 3<i>H</i>-pyrazole complexes [Ru­(η⁵-C₅H₅)­{η¹-NNC­(Ar1Ar2)­C­(COOR1)CH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>27</b>,<b> 28</b>). The complexes were characterized by spectroscopy and by X-ray crystal structure determinations of [Ru­(η⁵-C₅H₅)­{η¹-NC­(CN)­CH₂C­(Ph)­(<i>p</i>-tolyl)NH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>19b</b>), [Ru­(η⁵-C₅H₅)­{η²-CHCHCO­(O)CO}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>21</b>), and [Ru­(η⁵-C₅H₅)­{η¹-NNC­(C₁₂H₈)­CHCH}­(PPh₃)­{P­(OMe)₃}]­BPh₄ (<b>24c</b>)