Functionalization Of Cyclopalladated Ligands Using Secondary Phosphines And Meta-Chloroperoxybenzoic Acid

Cyclopalladation of organic ligands followed by reactions at the C–Pd bond with MPR2 (M = Li, K, or H) or other reagents (e.g. oxidants) is a desirable strategy for the synthesis of hemilabile bidentate ligands due to the large library of known cyclopalladated complexes (CPCs). This dissertation is composed of three projects on the functionalization of cyclopalladated ligands. In the first study, a new method for (sp3)C–P bond formation using diphenylphosphine was studied. Conditions for the synthesis of aminophosphines were optimized for the reactions of dinuclear chloro-bridged (sp3)C–Pd CPCs and HPPh2. The best yields were obtained with 9 equivalents of phosphine in methylene chloride in the presence of cesium carbonate at 35 Ñ. The scope of the reaction was explored with a range of enantiopure and achiral C,N and C,P CPCs. The corresponding N,P and P,P ligands or their oxides were isolated in 30–65% yields. Reactions of HPPh2 in toluene with CPCs derived from D-camphor methyloxime and 2-tert-butyl-4,4-dimethyl-2-oxazoline provided unique mononuclear Pd(II) complexes with a terminal PPh2 ligand in 16 and 52% yield, respectively. The electronic and steric effect of secondary phosphines were studied in phosphination reactions of cyclopalladated ligands. HPR2 with electron-donating and -withdrawing aryl groups (R = p-MeOC6H4 or p-CF3C6H4), bulky groups (R = mesityl or 1-adamantyl) and non-equavalent substituents (R1 = t-Bu, R2 = Ph) were reacted with CPCs derived from N,N-dimethylbenzylamine and enantiopure L-fenchone methyloxime, 1-(N,N-dimethylamino)ethylphenyl, and di-2,4-tert-butyl-2-oxazoline. With large molar ratios of phosphine to CPC (9:1 or 4.5:1), C–PR2 bond formation occurred to produce the corresponding aminophosphines or phosphine oxides in 56–61% and 12–44% yields, respectively. For both (sp2)C–Pd and (sp3)C–Pd CPCs, the reaction was tolerant to electronic differences in the phosphine substituents, but the sterically hindered phosphines dimesitylphosphine and HPt-BuPh reacted only with the fenchone-derived CPC to give the N,P ligand products in 32 and 12% yield, respectively. Finally, an approach to the synthesis of N,O ligands was studied via the oxygenation of (S)-4-tert-butyl- and (S)-4-ethyl-2-phenyl-2-oxazoline CPCs with meta-chloroperoxybenzoic acid (m-CPBA). Reactions were performed at room temperature in methylene chloride, ethyl acetate, or acetonitrile followed by workup with lithium chloride. Oxidation products formed in these reactions included dinuclear complexes (S,S)-di-μ-Cl(κ2-N,O)2Pd2, (S,S)-di-μ-oxo(κ2-N,O)2Pd2Cl2, and (S,S)-di-μ-(m-Cl-C6H4CO2)(κ2-N,O)2Pd2, as well as mononuclear derivatives (S,S)-bis(κ2-N,O)Pd and dinuclear monooxidation complexes (S,S)-di-μ-Cl(κ2-N,O)(κ2-C,N)Pd2. Each complex was isolated in low yield (6−46%) with the combined yield of oxidation products reaching up to 64%. The best selectivity in product distribution was observed for the reactions of μ-OAc-CPCs with 2.7 equivalents of m-CPBA in acetonitrile. All new compounds were characterized by 1H, 13C{1H}, and 31P{1H} NMR spectrometry, and their purity was proven by satisfactory elemental analysis. X-ray crystallographic data were obtained for a new cyclopalladated complex derived from O-methyloxime L-fenchone having HP(mesityl)2 as an ancillary ligand

Communications and media services

NASA's internal and external communication methods are reviewed. NASA information services for the media, for the public, and for employees are discussed. Consideration is given to electron information distribution, the NASA TV-audio system, the NASA broadcast news service, astronaut appearances, technology and information exhibits, speaker services, and NASA news reports for internal communications. Also, the NASA worldwide electronic mail network is described and trends for future NASA communications and media services are outlined

Role Of Triazoles In Wood Protection: Developing Analytical Approaches And Examining Sorption, Distribution, And Environmental Fate Of Fungicides

Triazoles are commonly used wood preservatives active against a wide range of fungi and bacteria. A full understanding of their diffusion and distribution in wood is essential for the development of enhanced treatment protocols ensuring long-term stability of wood products. Moreover, determining the fate of sorbed triazoles is critical to minimize their losses, but also to assess the environmental impact of the treated wood product. Herein, the diffusion, distribution and environmental fate of triazoles was studied using a radiolabeled tracer, 14C-uniformly-labeled tebuconazole. The wood-treatment technique was representative of industrial practices for the manufacturing of above-ground products such as windows and doors; specifically, ponderosa pine wood was dip-treated with a solvent-based, metal-free formulation. A three-step extraction protocol was developed for triazole isolation from wood along with sensitive analytical techniques for fungicide quantification including liquid scintillation counting and solid phase extraction followed by liquid chromatography - Time-of-flight mass spectrometry

A checklist of the fishes of the Monterey Bay area including Elkhorn Slough, the San Lorenzo, Pajaro and Salinas Rivers

An ichthyologist should be familiar with the literature on the regional distribution of fishes before he attempts identification of local collections. Occasionally specimens are captured that appear to be outside their geographic ranges; frequently research into the regional literature reveals that such individuals have been previously noted from the area and are thus within their reported ranges. The present checklist hopefully will assist other researchers in the identification of the fishes of Monterey Bay. The reference list also provides a brief historical review of the ichthyological research on fishes in the area. (Document has 84 pages

New Perspectives on Catholic and Democratic Voting Behavior Regarding Constitutional Same-Sex Marriage Bans

In the United States, constitutional same-sex marriage bans were a prominent political phenomenon in state and national politics for most of the 2000s, and were ballot items as recently as 2012. Traditionally, this has been addressed as it correlates to Republican party politics and the evangelical Protestant voting bloc, with some attention paid to the opposition to these measures by Democrats. In addition, Catholic voting is viewed as essentially a barometer of the general electorate, not only on this issue but on all issues other than reproductive rights. However, most of this research came out in response to the wave of amendments passed in 2006 and before multiple votes on these amendments in the following years. In addition, while researchers and media outlets pay great attention to the role of Protestant and Republican voters in these elections, there is little discussion of Catholic or Democratic voters\u27 activity regarding constitutional same-sex marriage bans. Reviewing data on religiosity, party affiliation, and voting on such amendments reveals unexpected and unusual connections between Catholic voters and the outcomes of these votes and that Democratic voting on same sex marriage was not unified until the amendments had become a somewhat common practice. In addition, it is a regularly held belief that acceptance of gay marriage by the general populous has been a steady, gradual process over the course of three decades. However, data from these elections suggests there has been at least one point of notable shift in voter behavior

Backstop geometry and accretionary mechanics of the Sunda margin

The convergent Sunda margin off Indonesia displays all geological features characteristic of an accretion-dominated subduction zone. A combined interpretation of prestack depth-migrated seismic reflection data and velocity information gained from refraction studies is supplemented by high-resolution bathymetric data and for the first time allows the exact mapping of backstop regimes. Initially, the outer high evolved as material was pushed against a static rigid arc framework backstop underlying a forearc basin. Increasing material strength of the outer high due to lithification formed a dynamic backstop, which controls accretion today. An out-of-sequence thrust marks the transition from the recent active frontal accretionary prism to the outer high and may be traced in the seismic and bathymetric data over the whole extent of the study area. The existence of a static as well as a dynamic backstop controls the forearc geometry and is associated with the segmentation of the forearc, which is observed in regimes of frontal as well as of oblique subduction. Mass balance calculations, which account for porosity changes and metamorphism, indicate a subduction history dominated by accretionary processes since the late Eocene. Accretion is associated with the low values of basal friction inferred for the Sunda margin. Structural investigations of conjugate fault planes indicate a very weak basal detachment. Effective stress analyses reveal that intrinsically weak material causes the high strength ratio of the detachment to the overlying sediments, whereas overpressuring within the frontal accretionary prism is negligible

Adaptive Merging on Phase Change Memory

Indexing is a well-known database technique used to facilitate data access and speed up query processing. Nevertheless, the construction and modification of indexes are very expensive. In traditional approaches, all records in the database table are equally covered by the index. It is not effective, since some records may be queried very often and some never. To avoid this problem, adaptive merging has been introduced. The key idea is to create index adaptively and incrementally as a side-product of query processing. As a result, the database table is indexed partially depending on the query workload. This paper faces a problem of adaptive merging for phase change memory (PCM). The most important features of this memory type are: limited write endurance and high write latency. As a consequence, adaptive merging should be investigated from the scratch. We solve this problem in two steps. First, we apply several PCM optimization techniques to the traditional adaptive merging approach. We prove that the proposed method (eAM) outperforms a traditional approach by 60%. After that, we invent the framework for adaptive merging (PAM) and a new PCM-optimized index. It further improves the system performance by 20% for databases where search queries interleave with data modifications

Tackling inequality is essential for behaviour change for net zero

Policies and psychological approaches often overemphasize individual agency, overlooking how socioeconomic inequality can constrain access to low-carbon alternatives. We argue that tackling these inequalities is urgent for impactful, equitable behaviour change

Patterns and Failure Modes of Fractures Resulting From Forced Folding of Cohesive Caprocks – Comparison of 2D vs. 3D and Single-vs. Multi-Layered Analog Experiments

Knowledge of the formation mechanisms and geometries of fracture systems in sedimentary rocks is crucial for understanding local and basin-scale fluid migration. Complex fracture networks can be caused by, for instance, forced folding of a competent sediment layer in response to magmatic sill intrusion, remobilisation of fluidized sand or fluid overpressure in underlying porous reservoir formations. The opening modes and geometries of the fractures mainly determine the bulk permeability and sealing capacity of the folded layer. In this study, we carried out laboratory analog experiments to better comprehend patterns and evolution of the fracture network during forced folding as well as differences of the fracture patterns between a 2D and 3D modelling approach and between a homogenous and a multi-layered cover. The experimental layering consisted of a lower reservoir layer and an upper cover, which was either a single high-cohesive layer or an alternation of low- and high-cohesive layers. The two configurations were tested in an apparatus allowing quasi-2D and 3D experiments. Streaming air from the base of the model and air injected through a needle valve was used to produce a regional and a local field of fluid overpressure in the layers. The experimental outcomes reveal that the evolution of the fracture network undergoes an initial phase characterized by the formation of a forced fold associated with dominantly compactive and tensile fractures. The second phase of the evolution is dominated by fracture breakthrough and overpressure release mainly along shear fractures. Structures observed in 2D cross sections can be related to their expressions on the surface of the 3D respective experiments. Furthermore, the experiments showed that the intrusion network is more complex and laterally extended in the case of a multi-layered cover. Our results can be instructive for detecting and predicting fracture patterns around shallow magmatic and sand intrusions as well as above underground fluid storage sites

Evaluating Consumer Acceptability of Various Muscles From the Beef Chuck and Rib

One hundred thirty-eight consumers evaluated steaks from the complexus (CX), infraspinatus (IF), serratus ventralis (SV), supraspinatus (SS), and triceps brachii (TB) from the wholesale beef chuck; the deep pectoral (DP) from the wholesale brisket; and the longissimus thoracis (LT) from the wholesale rib. The LT was used as a reference for comparison to the other muscles. Ten USDA Choice and ten USDA Select boneless boxed beef subprimals were used for each muscle. Subprimals were aged 14 d from box date, frozen, and cut into 2.5-cm-thick steaks. Consumers rated the IF highest (P \u3c 0.05) for overall like, tenderness, juiciness, and flavor, and assigned it the highest (P \u3c 0.05) price/0.45 kg. The TB also was rated higher (P \u3c 0.05) than the LT for overall like, tenderness, juiciness, flavor, and price/0.45 kg. The SV and CX were rated as being similar (P \u3c 0.05) to the LT for overall like, tenderness, juiciness, flavor, and price/0.45 kg. Consumers rated the SS lower (P \u3c 0.05) than the LT for tenderness, juiciness, flavor, and price. The DP was rated as the toughest, driest, and blandest (P \u3c 0.05), resulting in assignment of the lowest (P \u3c 0.05) price/0.45 kg. Differences in palatability ratings due to quality grade were found for several muscles; USDA Choice SV and SS were rated higher (P \u3c 0.05) for overall like, tenderness, and juiciness than USDA Select SV and SS. For the IF, USDA Choice was rated higher (P \u3c 0.05) for tenderness and juiciness than USDA Select. The USDA Choice TB was rated higher (P \u3c 0.05) for juiciness, and the USDA Choice DP was rated higher (P \u3c 0.05) for overall like, than their USDA Select counterparts. Tenderness, juiciness, and flavor ratings were correlated with overall like ratings (r = 0.84, 0.77, and 0.76, respectively) and with price (r = 0.73, 0.70, and 0.68, respectively). These results indicate the IF, TB, SV, and CX were acceptable, whereas and the SS and DP were unacceptable as steaks