Earth Sciences Commons^™

Microeukaryote Metabolism Across The Western North Atlantic Ocean Revealed Through Autonomous Underwater Profiling, Natalie R. Cohen, Arianna I. Krinos, Riss M. Kell, Rebecca J. Chmiel, Dawn M. Moran, Matthew R. Mcilvin, Paloma Z. Lopez, Brianna A. Alanis, Eric W. Chan, John A. Breier

School of Earth, Environmental, & Marine Sciences Faculty Publications

Microeukaryotes are key contributors to marine carbon cycling. Their physiology, ecology, and interactions with the chemical environment are poorly understood in offshore ecosystems, and especially in the deep ocean. Using the Autonomous Underwater Vehicle Clio, microbial communities along a 1050 km transect in the western North Atlantic Ocean were surveyed at 10–200 m vertical depth increments to capture metabolic signatures spanning oligotrophic, continental margin, and productive coastal ecosystems. Microeukaryotes were examined using a paired metatranscriptomic and metaproteomic approach. Here we show a diverse surface assemblage consisting of stramenopiles, dinoflagellates and ciliates represented in both the transcript and protein fractions, …

Robust Hydropower Planning Balances Energy Generation, Carbon Emissions And Sediment Connectivity In The Mekong River Basin, M. Tangi, Rafael Schmitt, Rafael M. Almeida, S. Bossi, Alexander S. Flecker, F. Sala, A. Castelletti

School of Earth, Environmental, & Marine Sciences Faculty Publications

We present a framework for strategic dam planning under uncertainty, which includes GHG emissions mitigation as a novel objective. We focus on the Mekong River Basin, a fast‐developing region heavily relying on river‐derived ecosystem services. We employ a multi‐objective evolutionary algorithm to identify strategic dam portfolios for different hydropower expansion targets, using process‐related and statistical models to derive indicators of sediment supply disruption and GHG emissions. We introduce a robust optimization approach that explores variations in optimal portfolio compositions for more than 5,000 state‐of‐ the‐world configurations, regarding sediment origins and trapping and GHG emissions. Thus, we can rank dam projects' …

Road Mitigation Structures Designed For Texas Ocelots: Influence Of Structural Characteristics And Environmental Factors On Non-Target Wildlife Usage, Anna Rivera Roy, Kevin W. Ryer, Md. Saydur Rahman, John H. Young Jr., Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Roads negatively impact wildlife through habitat fragmentation, loss of habitat connectivity, and wildlife-vehicle collisions, thus road mitigation structures, such as wildlife crossing structures (WCS), wildlife guards (WG), and fencing are commonly used to address this issue all over the world, including in the United States. In South Texas, such structures were built or modified along a State Highway in an effort to address road mortality for the endangered ocelot (Leopardus pardalis) and non-target wildlife species. The goal of this study was to examine temporal changes in wildlife interactions with WCS and WG during and after their construction and …

Red Harvester Ant, Pogonomyrmex Barbatus, Nests Impact Soil Compaction But Not Temperature In Peri-Urban Habitats Of The Lower Rio Grande Valley, Geovanni Hernandez, Hannah J. Penn, Richard Cano, Lilly Victoria Elliott-Vidaurri, Robin A. Choudhury

School of Earth, Environmental, & Marine Sciences Faculty Publications

Ants are vital ecosystem engineers that can influence soil properties, subsequent soil processes, and associated biota via underground nest construction. Harvester ants consume seeds and are often found in arid areas. They frequently alter the soil chemistry and bulk density of the soils in and around their nest sites. Many species of harvester ants also intentionally remove vegetation around their nest openings, which creates cones or discs of bare soil that may further alter soil temperatures. However, much of the work to study the impacts of harvester ants on soil properties has occurred in shrubland and grassland settings rather than …

Agenda De Investigación Para El Manejo Sustentable Del Manglar En Tamaulipas, México [Research Agenda For The Sustainable Management Of Mangroves In Tamaulipas, Mexico], Carlos Zamora-Tovar, Alejandro Fierro-Cabo, Glenda Nelly Requena-Lara

School of Earth, Environmental, & Marine Sciences Faculty Publications

Se presenta un análisis de la información ecológica disponible sobre los manglares de Tamaulipas, México. El objetivo fue establecer una línea base de conocimiento que defina el estado del arte a partir de la información publicada; actualizar la estructura forestal con datos propios observados en el año 2018; y determinar una agenda de investigación prioritaria para el manejo sostenible del ecosistema de man-glar, ecosistema de vital importancia por la gran variedad de recursos y servicios ambientales que aporta a la sociedad. La investigación bibliográfica recopiló 32 trabajos relevantes: 16 publicaciones formales, siete ediciones institucionales y nueve consideradas literaturas gris; recopilación …

Valorization Of Seafood Waste For Food Packaging Development, Zhijing Zhan, Yiming Feng, Jikai Zhao, Mingyu Qiao, Qing Jin

School of Earth, Environmental, & Marine Sciences Faculty Publications

Packaging plays a crucial role in protecting food by providing excellent mechanical properties as well as effectively blocking water vapor, oxygen, oil, and other contaminants. The low degradation of widely used petroleum-based plastics leads to environmental pollution and poses health risks. This has drawn interest in renewable biopolymers as sustainable alternatives. The seafood industry generates significant waste that is rich in bioactive substances like chitin, chitosan, gelatins, and alginate, which can replace synthetic polymers in food packaging. Although biopolymers offer biodegradability, biocompatibility, and non-toxicity, their films often lack mechanical and barrier properties compared with synthetic polymer films. This comprehensive review …

The Fishing Cat: New Insights On Distribution In The Northern Sector Of Chitwan National Park, Nepal, Rupesh Maharjan, Rama Mishra, Jhamak Bahadur Karki

School of Earth, Environmental, & Marine Sciences Faculty Publications

Fishing cat Prionailurus viverrinus (Bennett, 1833) is an elusive and medium-sized feline species with distinguished marking patterns on their head and body separating them from other feline species. Despite being distributed widely among diverse geographic locations, their abundance has declined due to significant habitat loss and human disturbances. There exists a substantial research gap regarding their abundance and distribution in Nepal. In this article, we presented the updated documentation of the fishing cat distribution in the northern sector of Chitwan National Park through our species-focused camera trapping survey. The study was carried out between April and May 2021 with a …

Review Of Agricultural Biomass Burning And Its Impact On Air Quality In The Continental United States Of America, Sai Deepak Pinakana, Amit U. Raysoni, Alqamah Sayeed, Juan L. Gonzalez, Owen Temby, Dawid K. Wladyka, Katarzyna Sepielak

School of Earth, Environmental, & Marine Sciences Faculty Publications

Burning is a common method to dispose agricultural biomass residue. This practice is widely used by farmers during pre- and post-harvest seasons for crops such as wheat, rice, grass seed, soy, cotton, sugarcane, and corn. Farmers choose this method because it is cost and time effective. These burning activities emit several types of pollutants into the atmosphere, including CH4, SOx, NOx, CO, CO2, and particulate matter of different sizes (i.e., PM1, PM2.5 and PM10). Globally, the United States of America ranks third, preceded by China and India, in greenhouse gas emissions due to agricultural burning activities. According to the 2020 …

Urban Soil Compaction Remediation By Shallow Tillage And Compost In Hydroseeded Lawn, James Jihoon Kang, Adam Flores, Engil Isadora Pujol Pereira, Jungseok Ho

School of Earth, Environmental, & Marine Sciences Faculty Publications

Construction activities often involve removal of topsoil and compaction of the exposed soil by heavy equipments. Such compacted soils with low organic matter can lead to low infiltration and poor vegetation establishment. The objective of this study was to investigate the efficacy of tillage (shallow till) and compost on soil physical and biological properties in a hydroseeded lawn as a post-construction best management practice for soil compaction remediation. The experimental site received a total of four land treatments in five replicated trials and it was hydroseeded with common Bermuda grass: 1) No Tillage + Compost (NT-C), 2) No Tillage + …

A Pilot Study On Particulate Matter Concentrations From Cooking And Its Effects On Indoor Air Pollution In A Mexican American Household In Mission, South Texas, Usa, Sai Deepak Pinakana, Carlos Garcia Patlan, Esmeralda Mendez, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

This pilot study focuses on particulate matter (PM) while cooking in a South Texan household. Dishes such as Beef, Burger, Fish, Chicken, Egg Sandwich, and Hotdog were prepared. Indoor PM levels were compared with outdoor PM levels. A DustTrak DRX was used to monitor the PM released during the cooking process. PM2.5 levels were highest while cooking beef, 162.79 + 209.62 μg m−3. Hot Dog preparation resulted in the lowest PM2.5 concentration of 27.72 + 5.58 μg m−3. Indoor PM2.5 levels were observed to be greater in contrast to outdoor levels when compared to the outdoor levels (96 words).

Using Bayesian Multispecies Models To Evaluate Fish And Invertebrate Detection Probability And Distribution In The Hypersaline Bahia Grande Tidal Basin, Roy M. Ulibarri, Catherine M. Eckert, David Hicks, David Montagne, Brandon Jones, David R. Stewart

School of Earth, Environmental, & Marine Sciences Faculty Publications

Objective

In 2000, the Laguna Atascosa National Wildlife Refuge acquired the Bahia Grande (Texas) management unit, a space that had lain barren and arid for 70 years. A large cooperative partnership launched a restoration project to replenish the basin and recover its original tidal hydrology. In 2005, the construction of a pilot channel successfully restored water throughout the basin, and plans to eventually widen the channel were developed. Our study aims to evaluate an estuarine habitat restoration by assessing ecological drivers and the impacts on species diversity.

Methods

We evaluated species richness, detection/occupancy rates, and species–habitat relationships, and we estimated …

Amino-Modified Upcycled Biochar Achieves Selective Chromium Removal In Complex Aqueous Matrices, Kenneth Flores, Diego F. Gonzalez, Helia Magali Morales, Arnulfo Mar, Sergi Garcia-Segura, Jorge L. Gardea-Torresdey, Jason Parsons

School of Earth, Environmental, & Marine Sciences Faculty Publications

Chromium pollution of groundwater sources is a growing global issue, which correlates with various anthropogenic activities. Remediation of both the Cr(VI) and Cr(III), via adsorption technologies, has been championed in recent years due to ease of use, minimal energy requirements, and the potential to serve as a highly sustainable remediation technology. In the present study, a biochar sorbent sourced from pineapple skins, allowed for the upcycling of agricultural waste into water purification technology. The biochar material was chemically modified, through a green amination method, to produce an efficient and selective adsorbent for the removal of both Cr(VI) and Cr(III) from …

Biotechnology For Sustainable Materials: Innovating Today For A Greener Tomorrow, Shashi Kant Bhatia, Saurabh Bhatia, Maria Eugenia Inda-Webb, Konstantina Kourmentza, Tae Seok Moon, Vijai Singh, Vishal Ahuja, Jingbo Li, Sanjeet Mehariya, Jikai Zhao

School of Earth, Environmental, & Marine Sciences Faculty Publications

No abstract provided.

Year-Round Co2 Emissions From The Drawdown Area Of A Tropical Reservoir: Strong Seasonal And Spatial Variation, Ícaro Barbosa, José R. Paranaíba, Sebastian Sobek, Sarian Kosten, Rafael M. Almeida, Vitor Duque, Natália Mendonça, Nathan Barros, Raquel Mendonça

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• Drawdown areas emitted 80% of reservoir CO2 with just 1/5 area.

• Emissions from reservoir shorelines near forests were greater than from areas near grassland.

• CO2 emissions increase with the distance from the water.

• Estimates of reservoir drawdown CO2 flux vary by ∼ 300 % across the seasons examined here.

• There was no discernible difference in CO2 emissions between day and night-time.

• A significant increase in CO2 fluxes was observed 30 min after a rewetting event.

Abstract

A growing body of literature points to drawdown areas as important sources of atmospheric CO2 within reservoirs. Yet seasonal and temporal patterns of …

Disaster Plant Pathology: Smart Solutions For Threats To Global Plant Health From Natural And Human-Driven Disasters, Berea A. Etherton, Robin A. Choudhury, Ricardo I. Alcalá Briseño, Romaric A. Mouafo-Tchinda, Aaron I. Plex Sulá, Manoj Choudhury, Ashish Adhikari, Si Lin Lei, Nattapol Kraisitudomsook, Jacobo Robledo Buritica

School of Earth, Environmental, & Marine Sciences Faculty Publications

Disaster plant pathology addresses how natural and human-driven disasters impact plant diseases, and the requirements for smart management solutions. Local to global drivers of plant disease change in response to disasters, often creating environments more conducive to plant disease. Most disasters have indirect effects on plant health through factors such as disrupted supply chains and damaged infrastructure. There is also the potential for direct effects from disasters, such as pathogen or vector dispersal due to floods, hurricanes, and human migration driven by war. Pulse stressors such as hurricanes and war require rapid responses, while press stressors such as climate change …

Skimming Genomes For Systematics And Dna Barcodes Of Corals, Andrea M. Quattrini, Luke J. Mccartin, Erin E. Easton, Jeremy Horowitz, Herman H. Wirshing, Hailey Bowers, Kenneth Mitchell, María Del P. González-García, Makiri Sei, Catherine S. Mcfadden

School of Earth, Environmental, & Marine Sciences Faculty Publications

Numerous genomic methods developed over the past two decades have enabled the discovery and extraction of orthologous loci to help resolve phylogenetic relationships across various taxa and scales. Genome skimming (or low-coverage genome sequencing) is a promising method to not only extract high-copy loci but also 100s to 1000s of phylogenetically informative nuclear loci (e.g., ultraconserved elements [UCEs] and exons) from contemporary and museum samples. The subphylum Anthozoa, including important ecosystem engineers (e.g., stony corals, black corals, anemones, and octocorals) in the marine environment, is in critical need of phylogenetic resolution and thus might benefit from a genome-skimming approach. We …

Spatial Distribution And Movement Of Atlantic Tarpon (Megalops Atlanticus) In The Northern Gulf Of Mexico, Shane A. Stephens, Michael A. Dance, Michelle Zapp Sluis, Richard J. Kline, Matthew K. Streich, Gregory R. Stunz, Aaron J. Adams, R. J. David Wells, Jay R. Rooker

School of Earth, Environmental, & Marine Sciences Faculty Publications

Atlantic tarpon (Megalops atlanticus) are capable of long-distance migrations (hundreds of kilometers) but also exhibit resident behaviors in estuarine and coastal habitats. The aim of this study was to characterize the spatial distribution of juvenile tarpon and identify migration pathways of adult tarpon in the northern Gulf of Mexico. Spatial distribution of juvenile tarpon was investigated using gillnet data collected by Texas Parks and Wildlife Department (TPWD) over the past four decades. Generalized additive models (GAMs) indicated that salinity and water temperature played a significant role in tarpon presence, with tarpon occurrences peaking in the fall and increasing …

Exploitation Of Environmental Dna (Edna) For Ecotoxicological Research: A Critical Review On Edna Metabarcoding In Assessing Marine Pollution, Sakib Tahmid Rishan, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• eDNA describes the genetic material of organisms present in aquatic environments.

• eDNA metabarcoding characterizes DNA of various marine species from a single sample.

• eDNA has enormous promise for ecotoxicological research in marine environments.

Abstract

The rise in worldwide population has led to a noticeable spike in the production, consumption, and transportation of energy and food, contributing to elevated environmental pollution. Marine pollution is a significant global environmental issue with ongoing challenges, including plastic waste, oil spills, chemical pollutants, and nutrient runoff, threatening marine ecosystems, biodiversity, and human health. Pollution detection and assessment are crucial to understanding the state of …

Detection And Monitoring Of Plant Pathogens And Pests, Walter F. Mahaffee, Lindsey D. Thiessen, Kevin M. King, Robin A. Choudhury

School of Earth, Environmental, & Marine Sciences Faculty Publications

No abstract provided.

Salmonella In The Environment: A Review On Ecology, Antimicrobial Resistance, Seafood Contaminations, And Human Health Implications, Mohammad Maruf Billah, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Salmonella is a genus of Gram-negative bacteria that is responsible for numerous food poisoning outbreaks worldwide. With 93.8 million food-borne illnesses and 155,000 fatalities annually, it has emerged as a significant global public health issue. There are currently more than 2,500 distinct Salmonella serotypes, and more than half of them are associated with Salmonella enterica. An increasing global public health concern for humans and animals is antimicrobial resistance by Salmonella species worldwide. Salmonella infections can be lethal; conditioned with an increased prevalence of multi-drug resistant (MDR) strains in the future. The emergence of MDR Salmonella serotypes is considerably …

Integrating Remote Sensing With Ground-Based Observations To Quantify The Effects Of An Extreme Freeze Event On Black Mangroves (Avicennia Germinans) At The Landscape Scale, Melinda Martinez, Michael J. Osland, James B. Grace, Nicholas M. Enwright, Camille L. Stagg, Camille L. Stagg, Simen Kaalstad, Gordon H. Anderson, Elena A. Flores, Alejandro Fierro-Cabo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Climate change is altering the frequency and intensity of extreme weather events. Quantifying ecosystem responses to extreme events at the landscape scale is critical for understanding and responding to climate-driven change but is constrained by limited data availability. Here, we integrated remote sensing with ground-based observations to quantify landscape-scale vegetation damage from an extreme climatic event. We used ground- and satellite-based black mangrove (Avicennia germinans) leaf damage data from the northern Gulf of Mexico (USA and Mexico) to examine the effects of an extreme freeze in a region where black mangroves are expanding their range. The February 2021 …

Mangroves Of The Warm Temperate Northwest Atlantic, Daniel A. Friess, Ena L. Suárez, Anna R. Armitage, Cheryl Doughty, Laura C. Feher, Ilka C. Feller, Alejandro Fierro, Kara R. Radabaugh, Lorae T. Simpson, William C. V Vervaeke, Carlos Zamora-Tovar

School of Earth, Environmental, & Marine Sciences Faculty Publications

The ‘Mangroves of the Warm Temperate Northwest Atlantic’ province is a regional ecosystem subgroup (level 4 unit of the IUCN Global Ecosystem Typology). It includes the marine ecoregions of Carolinian and Northern Gulf of Mexico. The biota is characterized by 3 species of mangroves: Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle, and 1 mangrove associate Conocarpus erectus, though not all species are equally distributed throughout the province. Mangroves in this province cross the USA and Mexico and are quite unique, as they exist at the latitudinal range limit of the mangrove ecosystem. The majority of mangroves in this province are …

Assessing Tax Revenue Implications Of Environmental Policy: A Case Study Of China’S Channel City Policy, Yongwen Yang, Juhee Lee

School of Earth, Environmental, & Marine Sciences Faculty Publications

Recent studies suggest that while environmental policies yield positive environmental effects, they also incur costs for various entities. However, there is a gap in research regarding these policies’ financial impact from the government's perspective. To investigate the extent to which government tax revenue is affected by environmental policies, we employ the Difference-inDifferences (DID) method to estimate the impact of a regional air pollution control policy in China known as the Channel City Policy on the tax revenue of city governments. Our findings indicate that the Channel City Policy (CCP) enhances air quality by reducing PM2.5, SO2, and NOx concentrations by …

Managing Inter-Organizational Trust And Risk Perceptions In Transboundary Fisheries Governance Networks, Evelyn Roozee, Dongkyu Kim, Antonia Sohns, Jasper R. De Vries, Owen Temby, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

Transboundary fishery management represents a significant governance challenge that requires ongoing inter-organizational communication, collaboration, and collective action to ensure sustainability. Previous research suggests that different dimensions of perceived risk, trust, and control interact in complex ways to affect inter-organizational collaborative performance, providing an administrative ‘architecture’ that enables partners to share resources, engage in teamwork, resolve conflict, and coordinate tasks and responsibilities while also allaying their concerns about the alliance. However, the extent to which different control mechanisms influence trust and mitigate the perceived risks of collaboration between the diverse organizations involved in transboundary fisheries management remains unclear. This paper presents …

Observed Impacts Of Large Wind Farms On Grassland Carbon Cycling, Donghai Wu, Steven M. Grodsky, Wenfang Xu, Naijing Liu, Rafael M. Almeida, Liming Zhou, Lee M. Miller, Somnath Baidya Roy, Geng Xia, Anurag A. Agrawal

School of Earth, Environmental, & Marine Sciences Faculty Publications

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Activity Patterns Of The Endangered Amargosa Vole (Microtus Californicus Scripensis), Austin N. Roy, Anna D. Rivera Roy, Deana L. Clifford, Janet E. Foley

School of Earth, Environmental, & Marine Sciences Faculty Publications

Examining the activity patterns of wildlife is an important aspect of understanding the ecology of a species and may be especially important for species of conservation concern. We used remotely triggered cameras to describe the daily and seasonal activity patterns and examine ecological factors that influence the activity of the Amargosa Vole (Microtus californicus scirpensis), a California endemic listed federally and by the state as Endangered, and is a marsh habitatspecialist in the Mojave Desert. We found that vole activity was greatest during crepuscular periods, followed by nocturnal and diurnal periods. We saw strong seasonal effects, with the highest activity …

Effects Of Elevated Temperature On 8-Ohdg Expression In The American Oyster (Crassostrea Virginica): Induction Of Oxidative Stress Biomarkers, Cellular Apoptosis, Dna Damage And Γh2ax Signaling Pathways, Md Faizur Rahman, Mohammad Maruf Billah, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Global temperature is increasing due to anthropogenic activities and the effects of elevated temperature on DNA lesions are not well documented in marine organisms. The American oyster (Crassostrea virginica, an edible and commercially important marine mollusk) is an ideal shellfish species to study oxidative DNA lesions during heat stress. In this study, we examined the effects of elevated temperatures (24, 28, and 32 °C for one-week exposure) on heat shock protein-70 (HSP70, a biomarker of heat stress), 8-hydroxy-2’-deoxyguanosine (8-OHdG, a biomarker of pro-mutagenic DNA lesion), double-stranded DNA (dsDNA), γ-histone family member X (γH2AX, a molecular biomarker of DNA damage), …

Globally-Distributed Microbial Eukaryotes Exhibit Endemism At Deep-Sea Hydrothermal Vents, Sarah K. Hu, Amy R. Smith, Rika E. Anderson, Sean P. Sylva, Michael Setzer, Maria Steadmon, Kiana L. Frank, Eric W. Chan, Darlene S. S. Lim, John A. Breier

School of Earth, Environmental, & Marine Sciences Faculty Publications

Single-celled microbial eukaryotes inhabit deep-sea hydrothermal vent environments and play critical ecological roles in the vent-associated microbial food web. 18S rRNA amplicon sequencing of diffuse venting fluids from four geographically- and geochemically-distinct hydrothermal vent fields was applied to investigate community diversity patterns among protistan assemblages. The four vent fields include Axial Seamount at the Juan de Fuca Ridge, Sea Cliff and Apollo at the Gorda Ridge, all in the NE Pacific Ocean, and Piccard and Von Damm at the Mid-Cayman Rise in the Caribbean Sea. We describe species diversity patterns with respect to hydrothermal vent field and sample type, identify …

Effect Of Different Pre-Growth Temperatures On The Survival Kinetics Of Salmonella Enterica And Listeria Monocytogenes In Fresh-Cut Salad During Refrigerated Storage, Avninder Kaur, Veerachandra K. Yemmireddy

School of Earth, Environmental, & Marine Sciences Faculty Publications

The effect of the pre-growth temperature of bacterial cultures on their subsequent survival kinetics in fresh-cut produce during refrigerated storage was investigated in this study. Three-strain cocktails of Listeria monocytogenes and Salmonella enterica, cultured at different growth temperatures (4, 21, and 37 °C) were inoculated on fresh-cut mixed salad and on individual produce in the mixed salad. The inoculated samples were stored at 4 °C and 80 ± 2% relative humidity (RH) for up to 72 h and the growth, survival, or death kinetics were determined at regular intervals. The results indicate that depending upon the type of pathogen …

Ortho-Fluoro Or Ortho Effect? Oxidative Addition Of Zerovalent Nickel Into The C–Cn Bond Of Substituted Benzonitriles, Tülay Ateşin, William D. Jones, Abdurrahman C. Atesin

School of Earth, Environmental, & Marine Sciences Faculty Publications

A recent study of the oxidative addition of zerovalent Ni to the C–CN bond of F-substituted benzonitriles showed significantly increased stabilization of the C–CN oxidative addition products with o-F groups (−6.6 kcal/mol per o-F) compared to m-F groups (−1.8 kcal/mol per m-F). To answer the question of whether this is an o-F effect or an ortho effect, in this study the effect of CF3 and CH3 groups on the oxidative addition of the [Ni(dmpe)] fragment [dmpe = 1,2-bis(dimethylphosphino)ethane] to the C–CN bond of benzonitriles has been studied. A density functional theory study of the reaction …