Análisis comparativo del uso de las tecnologías de la información y comunicación (TIC), en la gestión empresarial de los hoteles ubicados en la ciudad de Estelí, Nicaragua entre los años 2008 y 2016

La presente investigación está dirigida al análisis de las Tecnologías de Información y Comunicación (TIC) en la gestión hotelera de los hoteles de la ciudad de Estelí, utilizando como referente un estudio realizado en 2008 y comparando resultados con el año 2016, es un estudio de tipo cuantitativo, se aplicaron 19 encuestas a gerentes, administradores de los hoteles y entrevistas para complementar los análisis estadísticos. Como resultado se encontró que hay cambios significativos en la implementación de nuevas tecnologías como: la incorporación de nuevos equipos tecnológicos (hardware), e incremento de programas (software) específicos para hoteles. El 30% de los encuestados afirmó que la principal limitante es la falta de capacitación y el 28% indica que los altos costos para incorporar las TIC, encontrando diferencia en las dificultades entre los dos años. La hipótesis planteada se acepta en un 84% las TIC han provocado cambios en la gestión empresarial y el uso de tecnología está dirigido al marketing de los hoteles a través del internet. Se proponen seis líneas estratégicas para la mejora del uso de las TIC

«Малобюджетний» маркетинг

В умовах сьогоднішньої економічної кризи, яка зачепила всі вітчизняні підприємства, та постійного зниження української національної валюти актуальними стають питання пошуку способів економії коштів. Вирішенням таких проблем може стати «мало бюджетний» маркетинг, який допоможе розвиватися підприємству з використанням мінімальної кількості ресурсів. «Малобюджетний» маркетинг – це маркетингові інструменти залучення й утримання клієнтів, які припускають мінімальні витрати, а іноді можна взагалі обійтися без бюджету

From Five to Five: Titanium Ketimine Complexes with Monoaza-butadiene η⁴‑Coordination Mode and Hidden η²‑Imine Reactivity

In the reactions of LTiCl₃ (L: Cp*, Cp), Mg, and PhNC­(<i>p</i>-tolyl)₂ (<b>1</b>) the formation of η⁴-ketimine complexes Cp*Ti­(Cl)­(η⁴-PhNC­(<i>p</i>-tolyl)₂) (<b>2a</b>) and CpTi­(Cl)­(η⁴-PhNC­(<i>p</i>-tolyl)₂) (<b>2b</b>) are observed. Their “nonclassic” five-membered titanium monoazabutadiene envelope coordination modes, involving one of the <i>p</i>-tolyl substituents, is confirmed by single crystal X-ray diffraction analysis of <b>2b</b>. In reactions of <b>2</b> with aldehydes, ketones, alkynes, carbodiimides, isocyanates, isothiocyanates, and imines five-membered titanacycles are formed in a regioselective manner. This behavior is in agreement with a hidden η²-imine reactivity. All reaction products are fully characterized, including single crystal X-ray diffraction studies. For the PhCCH insertion products (<b>4b</b>, <b>4c</b>) the formation of Ti–C­(Ph) units are observed. By insertion of the isocyanate CyNCO the formation of a Ti–N bond in <b>6a</b> is preferred in comparison to the insertion of the isothiocyanate PhNCS, where a Ti–S bond is formed (<b>7a</b>). By reacting <b>2a</b> with aldimine PhNC­(H)­(<i>p</i>-tolyl) the nonsymmetric titanaimidazolidine derivative <b>8a</b> is formed by subsequent ketimine–aldimine coupling. By derivatization of <b>2a</b> with LiN­(Me)­Cy the formation of a the titanadihydropyrrole <b>9a</b> is observed, caused by a 1,3-<i>H</i>-shift. <b>2</b> appears to be inert toward a broad range of terminal olefins. Reacting <b>2a</b> with allyl ethyl ether results in a spontaneous ether cleavage reaction to <b>10a</b>

Activation of 7‑Silanorbornadienes by N‑Heterocyclic Carbenes: A Selective Way to N‑Heterocyclic-Carbene-Stabilized Silylenes

The synthesis of hydridosilylenes Ter­(H)­Si: <b>3a</b> (Ter: 2,6-bis­(2,4,6-trimethylphenyl)­phenyl) and Ter*­(H)­Si: <b>3b</b> (Ter*: 2,6-bis­(2,4,6-tri<i>iso-</i>propylphenyl)­phenyl) stabilized by the N-heterocyclic carbene (NHC) ImMe₄ is reported. The synthesis of stabilized hydridosilylenes <b>3</b> was accomplished by a previously unknown NHC-induced fragmentation of silanorbornadiene derivatives. Structural studies of the stabilized silylenes <b>3</b> and of its Fe­(CO)₄ complex <b>12</b> accompanied by a theoretical analysis of their bonding situation indicate that stabilized silylenes such as <b>3</b> can be regarded as neutral silyl anion equivalents. A computational investigation of the reaction course indicate a virtual one-step reaction between the NHC and the silanorbornadiene. A theoretical assessment of the scope and limitations of this reaction suggests that it is general and can be used also for the synthesis of other carbene analogues such as germylenes and phosphinidenes

Formation of δ‑Lactones by Cerium-Catalyzed, Baeyer–Villiger-Type Coupling of β‑Oxoesters, Enol Acetates, and Dioxygen

Formation of δ-lactones is observed when cyclopentanone-2-carboxylates are converted in a cerium-catalyzed reaction with α-aryl vinyl acetates under oxidative conditions. The products of this transformation possess a 1,4-dicarbonyl constitution together with a quaternary carbon center. Atmospheric oxygen is the oxidant in this process, which can be regarded as ideal from economic and ecological points of view. Further advantages of this new C–C coupling and oxidation reaction are its operational simplicity and the application of nontoxic and inexpensive CeCl₃·7 H₂O as precatalyst. This so far unprecedented reaction is proposed to proceed via 1,2-dioxane derivatives, which decompose under formation of an oxycarbenium cation in a Baeyer–Villiger-type pathway. This mechanistic picture is supported by the observation that electron-rich (donor substituted or heteroaromatic) enol esters give higher yields than electron deficient congeners. Apart from 1,4-diketones and α-hydroxylated β-oxoesters formed as byproducts, the yields of δ-lactones range from moderate to good (up to 74%)

Sequential Multicomponent Reactions and a Cu-Mediated Rearrangement: Diastereoselective Synthesis of Tricyclic Ketones

A novel Cu-mediated rearrangement reaction based on bisamides containing a thiazolidine substructure opens the possibility for diastereoselective synthesis toward a tricyclic annulated and bridged heterocyclic system. The required precursors are easily synthesizable by a two-step synthetic pathway using the concept of sequential multicomponent reactions, i.e. the Asinger and Ugi reactions. Due to this synthesis strategy, a number of unique tricyclic heterocycles, characterized by high diversity, are synthesized in an effective manner

Zwitterionic d⁰ Metal Complexes [(Cy₂N)₃M]⁺[(μ-Me)B(C₆F₅)₃]⁻ (M = Ti, Zr, Hf) Derived from Tris(dicyclohexylamido)methyl Metal Precursors

The synthesis and characterization of tris­(dicyclohexyl)­amido hafnium complexes ClHf­(NCy₂)₃ (<b>1-Hf</b>) and MeHf­(NCy₂)₃ (<b>2-Hf</b>) are presented. The reactions of the group 4 derivatives of this compound class (MeM­(NCy₂)₃; M = Ti (<b>2-Ti</b>), Zr (<b>2-Zr</b>), Hf (<b>2-Hf</b>)) with B­(C₆F₅)₃ are investigated. Their reactions with strong Lewis acids lead to the first examples of zwitterionic group 4 complexes employing three amido ligands at the electrophilic metal center ([(Cy₂N)₃M]⁺[(μ-Me)­B­(C₆F₅)₃]⁻). The solid-state structures of all of the betaines (<b>3-Ti</b>, <b>3-Zr</b>, <b>3-Hf</b>) are presented and compared. In all homologues the methyl group is abstracted by the Lewis acid but remains in interaction with the electron-deficient metal center, resulting in a linearly bridging methyl group. The M···C distances of <b>3-M</b> are elongated by 0.25 Å (av) in comparison to <b>2-M</b>

Activation of 7‑Silanorbornadienes by N‑Heterocyclic Carbenes: A Selective Way to N‑Heterocyclic-Carbene-Stabilized Silylenes

The synthesis of hydridosilylenes Ter­(H)­Si: <b>3a</b> (Ter: 2,6-bis­(2,4,6-trimethylphenyl)­phenyl) and Ter*­(H)­Si: <b>3b</b> (Ter*: 2,6-bis­(2,4,6-tri<i>iso-</i>propylphenyl)­phenyl) stabilized by the N-heterocyclic carbene (NHC) ImMe₄ is reported. The synthesis of stabilized hydridosilylenes <b>3</b> was accomplished by a previously unknown NHC-induced fragmentation of silanorbornadiene derivatives. Structural studies of the stabilized silylenes <b>3</b> and of its Fe­(CO)₄ complex <b>12</b> accompanied by a theoretical analysis of their bonding situation indicate that stabilized silylenes such as <b>3</b> can be regarded as neutral silyl anion equivalents. A computational investigation of the reaction course indicate a virtual one-step reaction between the NHC and the silanorbornadiene. A theoretical assessment of the scope and limitations of this reaction suggests that it is general and can be used also for the synthesis of other carbene analogues such as germylenes and phosphinidenes

Hafnocene-based Bicyclo[2.1.1]hexene Germylenes – Formation, Reactivity, and Structural Flexibility

2,5-Disilylsubstituted germole dianions <b>1</b> react with hafnocene dichloride to give hafnocene-based bicyclo[2.1.1]­hexene germylenes <b>3</b>. Their formation proceeds via hafnocene-germylene complexes <b>2</b> that were identified by NMR and UV spectroscopy. Germylenes <b>3</b> are stabilized by homoconjugation between the empty 4p­(Ge) orbital and the π-bond of the innercyclic C²C³ double bond. This interaction can be understood as σ², π-coordination of the butadiene part to the dicoordinated germanium atom that leaves the 16e^– hafnocene moiety electronically unsaturated. We demonstrate that this new class of germylenes might serve as ligand to a variety of low-valent transition-metal complexes. The structure of the germylene ligand in complexes with Fe(0), Ni(0), and Au­(I) and in reaction products with N-heterocyclic carbenes showed an intriguing structural flexibility that allows to accommodate different electronic situations at the ligating germanium atom. The origin of this structural adaptability is the interplay between the topological flexible unsaturated germanium ring and the hafnocene group

Zwitterionic d⁰ Metal Complexes [(Cy₂N)₃M]⁺[(μ-Me)B(C₆F₅)₃]⁻ (M = Ti, Zr, Hf) Derived from Tris(dicyclohexylamido)methyl Metal Precursors

The synthesis and characterization of tris­(dicyclohexyl)­amido hafnium complexes ClHf­(NCy₂)₃ (<b>1-Hf</b>) and MeHf­(NCy₂)₃ (<b>2-Hf</b>) are presented. The reactions of the group 4 derivatives of this compound class (MeM­(NCy₂)₃; M = Ti (<b>2-Ti</b>), Zr (<b>2-Zr</b>), Hf (<b>2-Hf</b>)) with B­(C₆F₅)₃ are investigated. Their reactions with strong Lewis acids lead to the first examples of zwitterionic group 4 complexes employing three amido ligands at the electrophilic metal center ([(Cy₂N)₃M]⁺[(μ-Me)­B­(C₆F₅)₃]⁻). The solid-state structures of all of the betaines (<b>3-Ti</b>, <b>3-Zr</b>, <b>3-Hf</b>) are presented and compared. In all homologues the methyl group is abstracted by the Lewis acid but remains in interaction with the electron-deficient metal center, resulting in a linearly bridging methyl group. The M···C distances of <b>3-M</b> are elongated by 0.25 Å (av) in comparison to <b>2-M</b>