1,300 research outputs found
Part I. A Novel Synthesis of Dihydrojasmone. Part II. Polymethyleneketenedimers and Trimers.
Part I. A Novel Synthesis of Dihydrojasmone. — 3-Methylcyclopent-2-en-2-ol-l-one, a readily available substance of natural occurrence, was utilized in the synthesis of the well-known dihydrojasmone (2-n-aniyl-3-methylcyclopent-2-en-l-one). This was the first practical synthesis of dihydroJasmone which did not involve a condensation reaction, thus the possibility of obtaining an isomeric mixture of products was eliminated.
Acetylation of 3-methylcyclopent-2-en-2-ol-l-one with acetic anhydride gave 2-acetoxy-3-methylcyclopent-2-en-l-one, which was converted by the action of propylene oxide to 2-acetoxy-3-methylcyclopent-2-en-l-one propylene ketal. Saponification of this ketal gave 3- methyl-l,2-cyclopentanedione-l,l-propylene ketal, which served as a precursor to dihydrojasmone. Upon treatment of this compound with n-amylmagnesium chloride, followed by hydrolysis with ammonium chloride solution, 2-n-amyl-3-methylcyclopentan-2-ol-l-one propylene ketal was obtained. Dehydration and deketalization of the latter compound with sulfuric acid solution yielded dihydrojasmone.
Part II. Polymethyleneketene Dimers and Trimers. — An excellent method for the preparation of ketoketene dimers involves the dehydrohalogenation of an acyl chloride with triethylamine. The reaction of cyclopropanecarbonyl chloride with triethylamine gave no dimer but instead a solid product, presumably the acyl ammonium chloride, which reacted with aniline to form cyclopropanecarboxanilide. Cyclobutanecarbonyl chloride and triethylamine yielded at temperatures below 25® a similar addition compound which gave cyclobutanecarboxanilide when treated with aniline. When the latter reaction was carried out at a higher temperature, dispiro [3.1.3.1] decane-5,10-dione was obtained. Dispiro [3.1.3.1] decane-5,10-dione, trimethyleneketene dimer, underwent cleavage and decarboxylation in alkali to give dicyclobutyl ketone. The ketone was obtained without acidification of the alkaline solution, which is generally necessary for the decarboxylation of a β-keto acid in the form of its sodium salt. A mechanism was proposed for its formation. Trimethyleneketene dimer reacted with ethanol in the presence of a catalytic amount of base to give ethyl l- (cyclobutanecarbonyl)cyclobutanecarboxylate, and was reduced to the corresponding glycol, dispiro [3.1.3.1] decane-5,10-diol with lithium aluminum hydride.
It is known that dimethylketene dimer, tetramethyl-l,3-cyclobutanedione, when treated with a catalytic amount of sodium methoxide, yields the cyclic trimer, hexamethyl-l,3,5-cyclohexanetrione. In the present investigation, this base-catalyzed process was utilized in the synthesis of trimethyleneketene trimer, trispiro [3.1.3.1.3.1] pentadecane-5,10,15-trione, from trimethyleneketene dimer.
In this study it was found that the alkaline hydrolysis of dimethylketene trimer with barium hydroxide gave 2,4,4,6-tetramethylheptan-3,5-dione. Trimethyleneketene trimer, upon treatment with the same reagent gave l, l (dicyclobutanecarb6nyl) cyclobutane and dicyclobutyl ketone. Ethanolysis of trimethyleneketene trimer gave ethyl 1-[1-(cyclobutanecarbonyl)cyclobutanecarbonyl] cyclobutanecarboxylate. Reduction of the trimer was accomplished with lithium aluminum hydride to give trispiro [3.1.3.1.3.1] pentadecane-5,10,15- triol.
Tetramethyleneketene dimer, dispiro [4.1.4.1] dodecane-6,12-dione, a known compound, was the only product isolated in an attempted synthesis of tetramethyleneketene monomer by dehydrohalogenation of cyclopentanecarbonyl chloride with triethylamine. The dimer underwent cleavage and decarboxylation when treated with alkali to give dicyclopentyl ketone.
Only one polymethylene ketene, pentamethyleneketene, has been reported in the literature. It was found that hexamethyleneketene could be synthesized by dehydrohalogenation of cycloheptanecarbonyl chloride with triethylamine. This monomer reacted with aniline to give cycloheptanecarboxanilide, and gave with cyclopentadiene a cycloaddition product, hexamethylenebicyclo [3.2.0] hept-3-en-l-one. Hexamethyleneketene dimerized upon standing to give dispiro- [6.1.6.1] hexadecane-8, l6-dione which underwent reduction with lithium aluminum hydride to give the corresponding glycol, dispiro [6.1.6.1] hexadecane-8,l6- triol
Effect of non-nicotinic moist snuff replacement and lobeline on withdrawal symptoms during 48-h smokeless tobacco deprivation
The present study investigated the effects of two herbal components (BACCOFFTM and DIPSTOP ™) of a commercially available smokeless tobacco treatment program for reducing subjective withdrawal symptoms during deprivation. One component, BACCOFF™, is a non-nicotinic chew. The second component, DIPSTOP™, is a liquid containing the alkaloid lobeline, which to some extent mimics peripheral nicotinic effects. All participants (N = 22 males) were placed in four conditions: BACCOFF™ + DIPSTOP™, BACCOFF™ + placebo control, DIPSTOP™ only, and placebo control only. The conditions involved 48 h of deprivation, and subjects were exposed to one condition per week for 4 weeks. Withdrawal measures were taken at baseline, 24 h, and 48 h of deprivation. Individuals were randomly assigned, and conditions were counterbalanced. Results showed that BACCOFF™, as compared with DIPSTOP™, significantly reduced withdrawal symptoms but not craving. These data suggest that behavioral/sensory substitutes’ influence on withdrawal might be routed through the product’s ability to approximate the preferred moist snuff
Evaluation of clinical prediction models (part 1):from development to external validation
Evaluating the performance of a clinical prediction model is crucial to establish its predictive accuracy in the populations and settings intended for use. In this article, the first in a three part series, Collins and colleagues describe the importance of a meaningful evaluation using internal, internal-external, and external validation, as well as exploring heterogeneity, fairness, and generalisability in model performance
Imaging in population science: cardiovascular magnetic resonance in 100,000 participants of UK Biobank - rationale, challenges and approaches
PMCID: PMC3668194SEP was directly funded by the National Institute for Health Research
Cardiovascular Biomedical Research Unit at Barts. SN acknowledges support
from the Oxford NIHR Biomedical Research Centre and from the Oxford
British Heart Foundation Centre of Research Excellence. SP and PL are
funded by a BHF Senior Clinical Research fellowship. RC is supported by a
BHF Research Chair and acknowledges the support of the Oxford BHF Centre
for Research Excellence and the MRC and Wellcome Trust. PMM gratefully
acknowledges training fellowships supporting his laboratory from the
Wellcome Trust, GlaxoSmithKline and the Medical Research Council
1995 CSREES Reports
The 1995 edition of the CSREES Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Factors Affecting the Quality of IQF Blueberries
2. Preventing the Bleeding of Blueberry Fruit in Bakery Products
3. Removing Water from Blueberries Before Freezing
4. Determination of Pesticide Residue Levels in Freshly Harvested and Processed Lowbush Blueberries
5. Industrial Ingredients from Cull Blueberries
6. Application of Heat as a Method of Controlling Secondary Pest Insects on Lowbush Blueberries
7. The Phenology and Biology of Bumble Bees, Bombus, spp., that Pollinate Lowbush blueberry, Vaccinium spp., in Maine
8. Pollination Ecology of Lowbush Blueberry in Maine
9. Effects of Irrigation on Lowbush Blueberry Yield
10. Effect of Brief Warming Treatments on Late Winter Low-Temperature Tolerance of Native Lowbush Blueberry
11. Correlation of Late-winter/Early-spring Cold Hardiness with Date of Flowering
12. Evaluation of Cold Tolerance of Opening Flowers of Lowbush Blueberry
13. Influence of Flower Delaying Sprays on Seasonal Variation of Low Temperature Tolerance in Lowbush Blueberry
14. Effect of Various Levels of Disbudding on Yield of Lowbush Blueberry
15. Effect of Boron and the Polyamine Putrescine on Lowbush Blueberry Fruit Set and Yield
16. Effect of Boron and the Polyamine Putrescine on Extending the Receptivity of Lowbush Blueberry Blossoms
17. Effect of Soil pH on Nutrient Uptake
18. Correcting Boron Deficiency - missing
19. Phosphorus Uptake
20. Evaluation of Hexazinone Formulation on Soil Movement and Weed Control
21. Effect of Time of Fall Pruning on Growth and Productivity of Blueberries
22. Hexazinone Ground Water Survey
23. Effect of hexazinone formulation on movement through the soil profile
24. Evaluation of Tribenuron Methyl for Bunchberry Control
25. Evaluation of Tribenuron Methyl Commercial Applications for Bunchberry Control
26. Effectiveness of Resin-Exchange Columns to Determine Efficacy in Removing Hexazinone from Well Water
27. Effect of Clopyralid for Vetch Control
28. Evaluation of Tribenuron Methyl/Velpar® Tank Mix for Bunchberry Control
29. Blueberry Extension Education Progra
Maine Blueberry Advisory Committee Research Report
The 1990 edition of the Maine Blueberry Advisory Committee Research Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:
1. Biology and action thresholds of secondary blueberry pests
2. Control of blueberry maggot
3. Control of secondary blueberry pests
4. Application of steam as a method of controlling secondary pest insects on lowbush blueberry: a feasibility study
5. Pollination of the lowbush blueberry by native bees
6. Nitrogen-phosphorus study
7. Potassium study
8. Multiple cropping of wild stands
9. Phosphorus dose/response curve
10. Improvement in the color and texture of the canned blueberry
11. The effect of fertilization and irrigation on blueberry fruit quality
12. Investigation of preprocess changes (chemical, microbiological, and/or physical) that could lead to the development of a simple and inexpensive method to measure preprocess berry spoilage
13. The effect of postharvest handling on the dietary fiber and ellagic acid content of lowbush blueberries
14. Determination of pesticide residue levels in freshly harvested and processed lowbush blueberries
15. Evaluation of Defoliating Diseases
16. Vacuum Sanitation for Disease Control
17. Evaluation and modification of commercial herbicide applications
18. Evaluation of the suitability of remote sensing to evaluate plant cover in lowbush blueberry fields
19. Evaluation of Sethoxydin (POAST) in lowbush blueberry fields
20. Seedling pruning study
21. Evaluation of norflurazon (SOLICAM) with or without hexazinone (VELPAR) for bunchberry control
22. Selective wiper and mechanical control of dogbane and bracken fern
23. Evaluation of norflurazon (SOLICAM) in fall vs spring for oatgrass control
24. Evaluation of sulfonyl urea herbicides for bunchberry control
25. Evaluation of postemergence applications of DPX-L5300 for bunchberry control
26. Effect of time of application and formulation of hexazinone (VELPAR) on blueberry and bunchberry
27. Investigations of lowbush blueberry fruit-bud cold hardiness
28. The economics of investing in irrigation for lowbush blueberries
29. Effects of irrigation on lowbush blueberry yield and quality
30. Groundwater and surface water development for blueberry irrigation
31. Design, fabrication and testing of an experimental sterilizer for blueberry field
1994 CSRS Research Reports/1994 Blueberry Tax Reports
The 1994 edition of the CSRS Research Reports/Blueberry Tax Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
CSRS Research Reports
1. Potential Uses for Green and Red Cull Blueberries
2. Preventing the Bleeding of Blueberry Fruit in Bakery Products
3. The Effect of Fertilization and Irrigation on Blueberry Fruit Quality
4. Determination of Pesticide Residue Levels in Freshly Harvested and Processed Lowbush Blueberries
5. The Effect of Mechanical Harvesting on Blueberry Fruit Quality
6. Removing Water from Blueberries Before Freezing
7. Application of Heat as a Method of Controlling Secondary Pest Insects in Lowbush Blueberries
8. Evaluation of Effectiveness of Eumenid Wasps for Biocontrol of Blueberry Pests
9. Pollination Ecology of Lowbush Blueberry in Maine
10. Fungicide Treatment for Control of Monilinia Blight
11. Field Sanitation for Control of Monilinia Blight
12. Cold-hardiness of Native Lowbush Blueberry
13. Phosphorus Dose/Response Curve
14. Multiple Cropping of Wild Blueberry Stands
15. Effect of Soil pH on Nutrient Uptake
16. Effect of Boron and Calcium on Lowbush Blueberry Fruit Set and Yield
17. Effect of Time of Fall Pruning on Growth and Productivity of Lowbush Blueberries
18. A Reinvestigation of the Economics of Mechanical Harvesting
19. Thresholds of Mechanical and Chemical Weed Controls in Wild Blueberries
20. Evaluation of Pressurized Rope Wick Master Wiper for Treating Weeds Growing Above Lowbush Blueberries
21. Evaluation of Infrared Burner for Selective Weed Control
Blueberry Tax Reports
22. Control of Blueberry Pest Insects
23. Biology and Action Thresholds of Secondary Blueberry Pest Insects
24. Pollination Ecology of Low bush Blueberry in Maine
25. Nitrogen-Phosphorus Study
26. Evaluation of Pronone 10G for Control of Weeds in Lowbush Blueberries
27. Evaluation of Tribenuron Methyl for Bunchberry Control
28. Evaluation of Pendimethalin for Control of Annual Grasses in Lowbush Blueberries
29. Evaluation of Time of Application of Clopyralid for Control of Vetch, and Effect on Flowering of Lowbush Blueberries
30. Hexazinone Ground Water survey
31. Blueberry Extension Program Base
32. Blueberry ICM Program for Hancock Count
1968: Abilene Christian College Bible Lectures - Full Text
CROWNING FIFTY YEARS”
Being the Fiftieth Annual ABILENE CHRISTIAN COLLEGE BIBLE LECTURES - 1968
J. D. THOMAS, LECTURESHIP DIRECTOR, EDITOR
Published by
ABILENE CHRISTIAN COLLEGE
ACC Station, Abilene, Texas 7960
1992 Blueberry Research Progress Reports
The 1992 Blueberry Research Progress Reports pertain to and report on research conducted in 1991, and were prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1992 CSRS Progress Reports:
1. Investigation of Groundwater Resources
2. Sprinkler Irrigation
3. Investigation of Preprocess Changes Leading to Berry Spoilage
4. Effect of Fertilization and Irrigation on Blueberry Quality
5. Effects of Calcium Salts and Citric Acid on Quality of Canned Lowbush Blueberries
6. Pollination of Lowbush Blueberry by Native Bees
7. Application of Heat for Controlling Insects
8. Investigations of Lowbush Blueberry Fruit Bud Cold-Hardiness
9. Steam Sterilization in Lowbush Blueberry Fields
10. Heat-Tolerant Molds
11. Vacuum Sanitation for Disease Control
12. Evaluation of Infrared Burner for Weed Control
13. Evaluation and Modification of Commercial Herbicide Wipers
14. Evaluation of Remote Sensing to Estimate Plant Cover in Lowbush Blueberry Fields
15. Comparison of Three Mechanical Blueberry Harvesters vs. Hand Raking
Advisory Committee Research Reports:
16. Biology and action thresholds of secondary blueberry insects
17. Control of secondary blueberry pests
18. Control of blueberry maggot
19. Effects of calcium salts and citric acid on the quality of canned lowbush blueberries
20. The effects of postharvest handling on the dietary fiber and ellagic acid content of lowbush blueberries
21. Investigation of preprocessing changes that could lead to development of simple and inexpensive method to measure preprocessing berry spoilage
22. Determination of pesticide residue levels in fresh and processed lowbush blueberries
23. Vacuum sanitation for disease control
24. Heat-tolerant molds
25. Seedling pruning study
26. Effect of time and rate of application of Clopyralid for control of Vetch in lowbush blueberries
27. Evaluation and modification of commercial herbicide wipers
28. Effect of time of application and formulation of Hexazinone (Velpar) on Blueberry and Bunchberry
29. Evaluation of postemergence applications of Tribenuron Methyl for Bunchberry control
30. Thresholds of Dogbane and Bracken Fern by mechanical and chemical control in lowbush blueberry fields
31. Evaluation of the suitability of remote sensing to evaluate plant cover in lowbush blueberry fields
32. Evalution of infrared burner for weed control
33. Effect of time of fall pruning on growth and productivity of blueberry and evaluation of infrared burner to prune blueberries
34. Effect of Boron on lowbush blueberry fruit set and yield
35. Winter injury protection by potassium
36. Multiple cropping of wild stands
37. Nitrogen-Phosphorus study
38. Phosphorus dose/response curve
39. Investigations of lowbush blueberry fruit bud cold-hardines
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