18 results on '"David C. Tyler"'
Search Results
2. Don't Fear the Reader: Librarian versus Interlibrary Loan Patron-Driven Acquisition of Print Books at an Academic Library by Relative Collecting Level and by Library of Congress Classes and Subclasses.
- Author
-
David C. Tyler, Joyce C. Melvin, MaryLou Epp, and Anita M. Kreps
- Published
- 2014
- Full Text
- View/download PDF
3. Academic library as learning space and as collection: A learning commons' effects on collections and related resources and services
- Author
-
Erica DeFrain, Brianna D. Hitt, DeeAnn Allison, and David C. Tyler
- Subjects
Information commons ,media_common.quotation_subject ,Library science ,Academic library ,Library and Information Sciences ,Space (commercial competition) ,Education ,Learning commons ,Taxonomy (general) ,Institution ,Interlibrary loan ,Sociology ,Repurposing ,media_common - Abstract
A tremendous amount has been written about the library as a learning space and about this model's two most popular outgrowths, the information commons and the learning commons. Little to nothing, however, has been written about how reshaping an academic/research library and repurposing library space affects the library as a collection, its resources, and its collections-related services. This study looks at the immediate impact of opening a learning commons in an academic/research library on circulation, document delivery and interlibrary loan requests for returnables, and on- and off-campus database accesses at one institution. Taxonomy Library Collection Management; Assessment
- Published
- 2019
- Full Text
- View/download PDF
4. Patron-Driven Acquisition and Circulation at an Academic Library: Interaction Effects and Circulation Performance of Print Books Acquired via Librarians’ Orders, Approval Plans, and Patrons’ Interlibrary Loan Requests
- Author
-
David C. Tyler, Joyce C. Melvin, Anita M. Kreps, MaryLou Epp, and Christina D. Falci
- Subjects
health care facilities, manpower, and services ,Strategy and Management ,Tying ,education ,Advertising ,Academic library ,Library and Information Sciences ,Patron-driven acquisition ,humanities ,health services administration ,Interlibrary loan ,Circulation (currency) ,Business ,health care economics and organizations - Abstract
Numerous publications on patron-driven acquisition (PDA) for print books and similar materials have reported that patron-requested materials circulate more. Tying circulation to selector may be failing to address the complex of factors that contributes to items' circulation. In the present study, the authors revisit a PDA program's data and to determine whether PDA print books' circulation advantage persists when the potential interactions of several additional variables are taken into account. As with prior studies, library patrons were significantly better predictors of circulation than were librarians or approval plans. However, librarians proved to be significantly better predictors than were approval plans.
- Published
- 2013
- Full Text
- View/download PDF
5. Just How Right Are the Customers? An Analysis of the Relative Performance of Patron-Initiated Interlibrary Loan Monograph Purchases
- Author
-
Joyce C. Melvin, David C. Tyler, Yang Xu, Anita M. Kreps, and MaryLou Epp
- Subjects
Finance ,business.industry ,Strategy and Management ,Value (economics) ,Interlibrary loan ,Circulation (currency) ,Library and Information Sciences ,Marketing ,business ,Collection development - Abstract
There has been a flurry of interest in programs for collection development through patron-initiated requests. However, some librarians have been concerned that such methods run the risk of producing idiosyncratic collections with poor usage and poor use value. The University of Nebraska-Lincoln Libraries have operated such a program through the Interlibrary Loan Department over a five-year period. The following study assesses the relative performance of the program's interlibrary loan–acquired monographs in terms of prices paid per rates of annual circulation, relative use at the topical level, and annual rates of circulation.
- Published
- 2010
- Full Text
- View/download PDF
6. EBSCO'sCommunication & Mass Media Complete: An Appreciable Improvement Over Previous Communication Studies Indexing?
- Author
-
Signe Boudreau, David C. Tyler, Misty Redinbaugh, and Katharine C. Potter
- Subjects
World Wide Web ,Information retrieval ,Computer science ,business.industry ,Communication studies ,Search engine indexing ,New product development ,General Social Sciences ,Library and Information Sciences ,business ,Field (computer science) ,Mass media - Abstract
In a prior edition of this study, we examined whether the established online communication studies indexes—Communication Abstracts, ComIndex, and ComAbstracts—provided a good avenue of access to the journal literature that researchers in the field cite and whether, where the current journal literature was concerned, that avenue of access might be equal or superior to that provided by large, multisubject online indexes. In this iteration of the study, we similarly address EBSCO's new product for communication studies, Communication & Mass Media Complete.
- Published
- 2008
- Full Text
- View/download PDF
7. Digging Deeper Still: Coverage of Archaeology from the United Kingdom and Ireland from 1950 to 2000+ in Discipline-Specific and Subject-Oriented Online Indexes
- Author
-
David C. Tyler, Susan M. Leach, Jennifer M. Kreifels, Katharine C. Potter, and Barbara Turner
- Subjects
Digging ,Kingdom ,History ,Field (Bourdieu) ,General Social Sciences ,Library science ,Subject (documents) ,Library and Information Sciences ,Archaeology - Abstract
Librarians, faculty, professional researchers, and students often encounter difficulties in locating pertinent journal articles for the field of archaeology. This article examines the coverage given by 13 discipline-specific and subject-oriented indexes available online over a 50-year interval to 89 archaeology journals originating in the United Kingdom and in Ireland. The coverage provided by the individual indexes and several of the larger issues surrounding the coverage of the field are discussed, and a few recommendations are offered.
- Published
- 2006
- Full Text
- View/download PDF
8. Want to See the Sites? Better Find a Better Guide
- Author
-
Scott Childers, Beth McNeil, Alicia Dostal, and David C. Tyler
- Subjects
Internet searching ,World Wide Web ,Search engine ,Internet resources ,business.industry ,Computer science ,Expert advice ,The Internet ,Library and Information Sciences ,Web resource ,business ,Web site - Abstract
This paper presents the results of a study of the utility of several popular search engines and of two newer search engines with respect to librarian-selected lists of Web resources and Internet searching behaviors. This study addresses whether said resources are returned where Internet searchers could reasonably be expected to find them and whether the search engines employed serve as acceptable substitutes for the expert advice of librarians. Search engines included in the study were Google, http://www.MSN.com, Yahoo, Lycos, AskJeeves, Icerocket, and Acoona. Searches for the study were based on the topics/titles of the “Internet Resources” columns from College & Research Libraries News for 2004. Finally, the paper addresses methodological concerns and proposes possible directions for further research.
- Published
- 2006
- Full Text
- View/download PDF
9. The Communication Studies Researcher and the Communication Studies Indexes
- Author
-
Signe Boudreau, Susan M. Leach, and David C. Tyler
- Subjects
World Wide Web ,Computer science ,Communication studies ,General Social Sciences ,Library and Information Sciences ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,Field (computer science) - Abstract
The existence of widely available large, multi-subject, online databases calls into question the necessity for small, discipline-specific indexes to support research. This study attempts to determine whether the online Communication Studies indexes provide access to the journal literature that researchers in the field actually cite and whether, where the current journal literature is concerned, that access is in any way superior to that provided by large, multi-subject, online indexes.
- Published
- 2005
- Full Text
- View/download PDF
10. Caveat Relocator: A Practical Relocation Proposal to Save Space and Promote Electronic Resources
- Author
-
David C. Tyler and Brian L. Pytlik Zillig
- Subjects
World Wide Web ,Computer printing ,Computer science ,Collection management ,Interlibrary loan ,Electronic information ,Library and Information Sciences ,Space (commercial competition) ,Relocation ,Computer Science Applications - Abstract
Despite ever-increasing electronic information, space on library shelves continues to be a problem. This article discusses one library's efforts to find space on overcrowded library shelves by moving selected resources to off-site storage and at the same time promoting use of electronic resources, namely the electronic journals that make up the JSTOR database. Issues explored include in-house use of bound periodicals, circulation statistics, interlibrary loan requests, and computer printing vs. photocopying for print titles available through JSTOR.
- Published
- 2003
- Full Text
- View/download PDF
11. Librarians and Link Rot: A Comparative Analysis with Some Methodological Considerations
- Author
-
David C. Tyler and Beth McNeil
- Subjects
World Wide Web ,Library science ,Sociology ,Library and Information Sciences ,Web resource ,Link rot - Abstract
The longevity of printed guides to resources on the web is a topic of some concern to all librarians. This paper attempts to determine whether guides created by specialist librarians perform better than randomly assembled lists of resources (assembled solely for the purpose of web studies), commercially created guides ('Best of the web'-type publications), and guides prepared by specialists in library science and other fields. The paper also attempts to determine whether the characteristics of included web resources have an impact on guides' longevity. Lastly, the paper addresses methodological issues of concern to this and similar studies.
- Published
- 2003
- Full Text
- View/download PDF
12. Managing Biodivsity as Part of the PNG LNG Project
- Author
-
David C. Tyler and Steven J. Whisker
- Subjects
business.industry ,Environmental resource management ,Biodiversity ,Business ,Environmental planning - Abstract
The Papua New Guinea LNG (PNG LNG) Project is under development by Esso Highlands Limited (EHL), a subsidiary of Exxon Mobil Corporation, in an area of high biodiversity significance and conservation value. This paper provides an overview of EHL's Biodiversity Strategy, describes how it has been implemented to date and presents EHL's guiding principles and forward plans for the Biodiversity Offset Program. EHL has prepared and is implementing a Biodiversity Strategy which outlines how terrestrial biodiversity has been and will continue to be managed as part of the Project. The Biodiversity Strategy is consistent with ExxonMobil's broader focus on achieving excellence when operating in sensitive environments. The Biodiversity Strategy is designed to meet International Finance Corporation (IFC) Performance Standard 6: Biodiversity Conservation and Sustainable Natural Resource Management (2006). This is consistent with the financing of the Project by a number of Export Credit Agencies and commercial banks which subscribe to the Equator Principles and apply IFC Performance Standards. The Biodiversity Strategy is based on a process of identifying biodiversity values in the Project area, identifying potential risks and impacts to these values which may arise as part of the Project and avoiding and mitigating the identified risks during design, construction and production. Impacts which cannot be avoided or mitigated (residual impacts) are to be offset. The Biodiversity Strategy also outlines EHL's long term biodiversity monitoring program. EHL is currently developing a Biodiversity Offset Delivery Plan, with assistance from Conservation International, and the plan will set out details of the offset program. Offsets are to be tied to residual impacts, which, as identified in the Project Environmental Impact Statement (EIS) are likely to be direct impacts (overall habitat loss and impacts to fauna) and indirect impacts (potential introduction and spread of alien invasive species, and enhanced access). Consultation with stakeholders and interested parties is a key component in the development of the Biodiversity Strategy and the Biodiversity Offset Delivery Plan. It is EHL's intent that international and local NGO will be involved in the delivery of biodiversity offset projects.
- Published
- 2012
- Full Text
- View/download PDF
13. Research and Monitoring to Support Responsible Offshore Oil and Gas Development in the Presence of the Western Gray Whale Population off Northeast Sakhalin, Russia
- Author
-
Jennifer Dupont, Gary H. Isaksen, David C. Tyler, Daniel E. Egging, Ervin Kalinin, Bella Blackman, Mikhail Danilov, Rodger Melton, Elena Gauptman, Sandra Werner, Mike Swindoll, and Michael Jenkerson
- Subjects
education.field_of_study ,Oceanography ,Geography ,Population ,Gray whale ,education ,Offshore oil and gas - Abstract
Exxon Neftegas Limited (ENL) is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Okhotsk Sea, Russia. These projects are located in proximity to a habitat used by the Korean-Okhotsk or Western North Pacific gray whales (Eschrichtius robustus), hereafter referred to as the Western Gray Whale (WGW). The WGW population is listed as endangered in the Russian Red Book and as critically endangered by the International Union for the Conservation of Nature (IUCN). ENL has a long history of monitoring the WGWs in partnership with Sakhalin Energy Investment Company, Ltd. (SEIC), resulting in one of the most comprehensive data sets on marine mammal ecology and anthropogenic impacts at both the individual and population levels. The robust dataset resulted in the development and implementation of mitigation plans to address major risks to the population and, through a recent tagging / satellite monitored telemetry effort, provided important insights into Pacific basin-scale movements of the population. This paper provides an overview of: ENL's initial studies and protection plans to address WGW ecological data gaps and risks to the population.Methodologies of and summary results from the comprehensive ENL-SEIC Joint Monitoring Program to monitor impacts of industry operations.Results from a tagging / satellite monitored telemetry program funded by ENL and SEIC to better assess the risks to the WGW population across its annual life cycle, including areas outside the immediate vicinity of industry operations off Sakhalin Island. The start of offshore commercial oil and gas development on the northeastern Sakhalin Shelf in the mid-1990's necessitated a thorough review of environmental and socioeconomic conditions throughout the project area (Sakhalin Island, adjacent seas, and a portion of the Khabarovsk Krai; Figure 1). ENL, operator of the Sakhalin-1 Consortium, is committed to conducting business in a manner that is compatible with the balanced environmental and economic needs of the communities in which it operates. In preparation for a comprehensive Environmental Impact Assessment (EIA) and State Ecological Expert Review (SEER) process, as required under Russian Law, ENL initiated studies of the environmental and socioeconomic sensitivities of the Sakhalin-1 Project area. WGWs (Figure 2) were identified as a species of primary concern on the northeast Sakhalin shelf due to its listing as critically endangered by IUCN and Category I (endangered) listing in the Red Book of the Russian Federation. In addition, a joint declaration of the Gore–Chernomyrdin Commission, "On Measures to Ensure Biodiversity Conservation in the Sakhalin Island Area" was issued in February 1997, with one specific goal listed as enhancing research cooperation on the WGWs. ENL evaluated the results and recommendations from the project EIA and SEER processes, as well as recommendations by the bilateral commission, and co-funded studies to increase the understanding of WGW ecology, and to monitor the impact of the Company's oil and gas developments on the WGW population. The preliminary study results were combined with existing knowledge from other regional researchers to form the basis for mitigation and monitoring for ENL's 3-D seismic surveys in 2001 for its Odoptu field off northeast Sakhalin.
- Published
- 2012
- Full Text
- View/download PDF
14. Project Management — Engaging the Hearts and Minds to 'Protect Tomorrow. Today.'
- Author
-
Lillian Boog, David C. Tyler, Benjamin Wood, and Douglas R. Callon
- Subjects
Engineering ,business.industry ,Engineering ethics ,Project management ,business - Abstract
ExxonMobil Development Company (EMDC) is in the project management business. The company currently manages a portfolio of more than 120 projects on five continents. Today's projects are often progressed in sensitive environments, against a backdrop of complex regulatory frameworks and fragile socioeconomic settings. The manner in which these risks are identified, assessed, and managed can significantly impact the success of a project and, importantly, its longer-term operations. Engaging the hearts and minds of our project teams early on is the key to successfully managing these stakeholder risks. Just a few of EMDC's strategies described in this paper include: Leadership: Established a Socioeconomic Center of Excellence for all Upstream activitiesProcess: Formalized a screening process during concept selection focused on environmental and socioeconomic alternativesCollaboration: Created an online "suitcase" for project teams with key guidance, tools, and project examplesLearning: Developed a flexible training framework for project management using targeted "leadership briefings" Our strategies can help small and large project operators and contractors engage the hearts and minds of their own people, enabling them to tackle the evolving challenges of key stakeholder risks. The strategies apply in developed and developing countries alike, at either greenfield or brownfield locations, and under any fiscal terms. The journey is ongoing but EMDC is seeing progress in managing this important aspect of our global business. The success of our work on Sakhalin Island has led to new resource opportunities across Russia. The Point Thomson Project on Alaska's North Slope has successfully deployed new practices and technologies to protect the environment. And while the world-class LNG project in PNG has been challenging on several fronts, these "heart and mind" strategies are steadily taking root.
- Published
- 2012
- Full Text
- View/download PDF
15. Integrating Premier Standards of Socioeconomic Management into Upstream Activities through Management Systems
- Author
-
Kelly J. Moynihan, Charlie Kominas, David C. Tyler, Miles J. Shaw, and Philip Brinkmann
- Subjects
Upstream (petroleum industry) ,Geography ,business.industry ,Environmental resource management ,Management system ,business ,Socioeconomic status - Abstract
Oil and gas industry projects have the potential to impact individuals, communities and the environment where they occur. Early identification, planning and engagement are essential to implement appropriate risk management-related avoidance and/or mitigation measures as well as identify and optimize opportunities to achieve positive socioeconomic outcomes. ExxonMobil recognizes that effective management of social and environmental issues is fundamental to the management of risk related to its major upstream projects and to achieving long-term Company success. Socioeconomic Management is the term ExxonMobil uses to describe its approach to managing local community impacts. Socioeconomic Management is a risk-based approach comprised of several core elements that include but are not limited to: adhering to internal corporate policies, expectations and standards; complying with applicable host country regulatory requirements, international conventions and universally recognized industry practices; engaging with external groups; and building local economic capacity. ExxonMobil's Upstream Socioeconomic Management process covers: Impact assessment and mitigation;Human rights;Community relations;Indigenous peoples;Cultural heritage and diversity;Land use and resettlement;Economic development; and,Transparency and corruption. Socioeconomic issues can be difficult to identify, predict, assess and consequently manage, and business challenges include, and are often dominated by, socioeconomic attributes. Industry data indicate that international oil and gas projects are often adversely impacted, from a cost and schedule perspective, by stakeholder-related issues. ExxonMobil's own experiences have reinforced that sufficient time and resources must be dedicated to manage socioeconomic issues. Early and frequent engagement with the appropriate external stakeholders is an important factor in addressing these challenges. What makes ExxonMobil successful is its commitment to carefully and systematically identify, plan for, and manage risk. This is accomplished by applying a rigorous management approach — the Operations Integrity Management System, or OIMS. OIMS integrates safety, security, health, environmental and social risk management into every aspect of ExxonMobil's business. ExxonMobil's approach to managing local community impacts is integrated into OIMS.
- Published
- 2012
- Full Text
- View/download PDF
16. SS - Sakhalin-1: Regulatory and Environmental Management
- Author
-
M. Romanova, David C. Tyler, D.E. Egging, B.E. Reep, M.J. Scott, M.E. Fedak, E. Gauptman, and J.E. O'Reilly
- Subjects
business.industry ,Environmental resource management ,business ,Environmental planning - Abstract
Abstract This paper reviews the environmental and regulatory performance of ExxonMobil Development Company (EMDC) and its contractors during Phase-1 development of the Sakhalin-1 Project Chayvo Field offshore Sakhalin Island, Russia, from 2002 through 2007. The Sakhalin-1 Project is being developed under a Production Sharing Agreement (PSA) with ExxonMobil's local affiliate, Exxon Neftegas Limited (ENL), serving as the operator for an international consortium of Russian, Japanese and Indian partners. 1 The Phase-1 development of Chayvo field is the first year-round offshore project to be completed in Russia. First oil was in October 2005 and the project reached full production by February 2007. To ensure good relationships and support from local, regional and federal government authorities, ENL implemented its global best practices for environmental performance and regulatory compliance. As measures of its success, ENL was awarded Foreign Project of the Year by the Russian publication, RusEnergy in 2006 and received the Excellence in Project Integration Award at the 2008 International Petroleum Technology Conference. This paper demonstrates the need for early, comprehensive planning for environmental performance and regulatory compliance, including project approvals and permitting. It describes Russia's dynamic and complex regulatory framework and underscores the value of local expertise and professional relationships with Russian authorities. This paper also offers lessons learned from ENL's efforts to monitor Western gray whales and Steller's sea eagles, its oil spill prevention planning, archaeology, public consultation and other programs. The information and related lessons learned may be useful for future oil and gas developments, and could help benchmark similar projects or identify issues that other operators might face. Introduction The Sakhalin-1 oil and gas development, located on the northeast shelf of Sakhalin Island, includes the Chayvo, Odoptu and Arkutun-Dagi fields. Together they contain an estimated 2.3 billion barrels (307 million tons) of oil and 17.1 trillion cubic feet (485 billion cubic meters) of natural gas. Although hydrocarbons were discovered offshore Sakhalin in the 1970s, the technology to produce them was not available. The current phase of exploration and development began when the production sharing agreement became effective in 1996. Exxon Neftegas Limited (30 percent) operates the Sakhalin-1 Project. The consortium includes two Russian companies, Sakhalinmorneftegas-Shelf (11.5 percent) and RN-Astra (8.5 percent), the Japanese company, SakhalinOil and Gas Development Co., Ltd. (30 percent) and India's ONGC Videsh Ltd. (20 percent). Both Russian partners are affiliates of Rosneft, the Russian state-owned oil company.
- Published
- 2009
- Full Text
- View/download PDF
17. SS: Sakhalin-1: Safety Leadership
- Author
-
Tatyana Salchenko, David C. Tyler, Daniel Duncan, and Joseph Silkowski
- Abstract
Abstract Maintaining a safe work environment in a harsh, remote construction environment is a challenge. Success requires leadership, commitment, and a well-defined safety management system. This paper is a summary of Sakhalin-1 Project safety success achieved as an integral part of the project's business objectives. The results demonstrate broad safety ownership by project team members and contractors, the spread of a proactive and caring safety culture, and a favorable view of ExxonMobil as a business partner in Russia. The paper also provides insight on some of the difficulties of working in sub-Arctic conditions with new contractors and a largely inexperienced and culturally-diverse workforce. Lessons learned and best practices are highlighted for potential use in future projects. Key points include the need for high level safety leadership and the visible involvement of senior project management. It shows the importance of clearly communicating your expectations and constantly promoting a culture in which business objectives never outweigh the need for safety. Introduction In late 1993, ExxonMobil affiliate Exxon Neftegas Limited (ENL), along with its Sakhalin-1 consortium partners SODECO, ONGC Videsh Limited, and Rosneft, signed a memorandum of understanding with the Russian Federation to begin technical and commercial discussions for development of three oil and gas fields off the eastern shore of Sakhalin Island. 1 Chayvo, located 5 to 15 kilometers offshore, was selected to be developed first, followed by the Odoptu and Arkutun-Dagi fields. Although the fields are in relatively shallow water, Sakhalin's Arctic winters threaten any offshore structures with thick sea ice and hurricane-force winds. The region is also prone to earthquakes. Given the project's remote location and environmental challenges, ExxonMobil Development Company and operator ENL took an innovative approach for developing Sakhalin-1. First, a land-based drilling rig with extended reach capabilities was designed and constructed by Parker Drilling. In the summer of 2003, the 22-story " Yastreb?? (Russian for " hawk??) began drilling the projects' first extended reach well from shore into the western portion of the Chayvo field. For its offshore drilling program, the project secured a mothballed concrete island drilling system that had formerly been used on Alaska's North Slope. The structure was towed to Khabarovsk Krai in Far East Russia, where it was made more resistant to ice and seismic events. From there it was towed to Korea, where a 12,000- metric-ton topsides facility was added. The new " Orlan?? (Russian for " Sea Eagle??) platform was then towed to the Chayvo field, where it began drilling in December of 2005. To process oil and gas from Sakhalin-1, ENL hired Fluor Daniel to build an Onshore Processing Facility (OPF) near the shore-based well site. The contract, awarded in December of 2003, called for a series of 36 equipment modules to be built at the Hyundai Heavy Industries fabrication yards in Ulsan South Korea and shipped to Sakhalin Island for assembly. The modular approach allowed the OPF to go from design to load out in just 34 months, much less time than it would have taken to build the plant on site.
- Published
- 2009
- Full Text
- View/download PDF
18. Chemistry of di- and tri-metal complexes with bridging carbene or carbyne ligands. Part 32. Reactions of the rhodium–tungsten complex [RhW(µ-CC6H4Me-4)(CO)3(η-C5H5)(η-C9H7)] with alkynes; X-ray crystal structure of [RhW{µ-C(C6H4Me-4)C(Ph)C(Ph)}(CO)2(η-C5H5)(η-C9H7)]
- Author
-
Michael Green, David C. Tyler, Judith A. K. Howard, F. Gordon A. Stone, and Simon J. Porter
- Subjects
chemistry.chemical_classification ,Chemistry ,Stereochemistry ,chemistry.chemical_element ,Carbyne ,General Chemistry ,Crystal structure ,Medicinal chemistry ,Rhodium ,chemistry.chemical_compound ,Cyclopentadienyl complex ,Tetraphenylcyclopentadienone ,Hexaphenylbenzene ,Inorganic compound ,Carbene - Abstract
The bimetal compound [RhW(µ-CR)(CO)3(η-C5H5)(η-C9H7)](R = C6H4Me-4, C9H7= indenyl) reacts with the alkynes R1CCR2(R1= R2= Ph or Me; R1= Ph, R2= H or Me) in toluene at ca. 50–80 °C to give the bridged complexes [RhW{µ-C(R)C(R1)C(R2)}(CO)2(η-C5H5)(η-C9H7)]. The molecular structure of the species obtained from PhCCPh was established by a single-crystal X-ray diffraction study. A Rh–W bond [2.754(1)A] is bridged by a three-carbon chain [mean C–C 1.439(8)A]. Whereas all the atoms of the chain are bound to the rhodium [2.105(6), 2.135(6), and 2.103(5)A], only the two end carbons are attached to the tungsten [2.175(5) and 2.196(6)A]. The tungsten atom carries two essentially orthogonal terminal carbonyl groups, as well as the cyclopentadienyl ring. The indenyl group is asymmetrically attached to the rhodium atom, with three short Rh–C [2.185(7), 2.198(7), and 2.204(7)A] and two long Rh–C [2.334(7) and 2.330(7)A] separations to the C5 ring, implying slippage towards an η3-bonding mode. Formation of [RhW{µ-C(R)C(Ph)C(Ph)}(CO)2(η-C5H5)(η-C5Me5)] from [RhW(µ-CR)(CO)3(η-C5H5)(η-C5Me5)] and PhCCPh requires forcing conditions (100 °C, 5 d in toluene), and side-reactions occur to yield hexaphenylbenzene, [Rh(CO)2(η-C5Me5)], and the tetraphenylcyclopentadienone complex [Rh(µ-C4Ph4CO)(η-C5Me5)]. The reaction between [RhW(µ-CR)(CO)3(η-C5H5)(η-C9H7)] and [W(CR)(CO)2(η-C5H5)] has also been investigated. With heptane as solvent, the products are the trimetal complex [Rh2W(µ3-CR)(µ-CO)(CO)2(η-C5H5)(η-C9H7)2], the alkyne-bridged complex [W2(µ-RC2R)(CO)4(η-C5H5)2], and a compound formulated as [W2{µ-C(R)C(O)C(R)}(CO)4(η-C5H5)2]. Spectroscopic data (i.r., 1H and 13C-{1H} n.m.r.) for the new compounds are reported and discussed.
- Published
- 1984
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.