Описание: Abstract: Cycloadditions involving fluoroallenes are extremely useful mechanistic probes. Due to the high reactivity of these allenes and the small size of their fluorine substituents, cycloadditions of fluoroallenes are free from many of the ambiguities surrounding analogous studies by previous workers. Styrene and 1,1-difluoroallene, DFA, undergo clean reactions between 60o and 100oC to give good yields (approx. 60%) of two cylcloadducts: 2,2-difluoro-3-phenyl-1-methylenecyclobutane (major) and 3-phenyl-1-(difluoromethylene)cyclobutane (minor). Similar experiments comparing the reactions of p-nitro and p-methoxystyrene with the above results give relative reactivities of 2.1 and 1.3, respectively. The 2]2] cycloaddition of DFA with Z-β-deuteriostyrene gives the expected products in an 82:18 ratio with stereochemical ratios of 58:42 and 79:21, respectively, at 80oC. A mechanism involving two kinetically distinguishable diradicals is proposed to rationalize the results. The reaction of DFA with 1-cyanovinyl acetate, a "capto-dative" reagent is also studied and found to give results similar to the styrene reactions. N-Methyl, N-phenyl, and N-(2-naphthyl)-C-phenylnitrones undergo regiospecific C2-C3 dipolar cycloadditions with monofluoroallene, MFA, in nearly quantitative yields at 25oC. The average stereochemical ratio for the two 4-substituted isoxazolidines produced is 84:16 2% with the product from syn addition of MFA in excess. The stereochemical assignments of the products are made with the aid of difference nuclear Overhauser effect (NOE) experiments and an X-ray crystal structure. Extensive solvent and kinetic studies show that these are well-behaved second-order kinetic processes consistent with previously well-studied 1,3-dipolar cycloadditions. The reaction of MFA with diazomethane-d2 strongly favors the product from the syn addition (88:12 ratio), also. Consideration of transition-state dipole-dipole interactions and solvation phenomena show that the factors affecting the stereochemical outcome of all these 1,3-dipolar cycloadditions are extremely subtle. Finally, MFA undergoes Diels-Alder reactions with cyclopentadiene, butadiene, and furan to give a modest preference for the syn adduct (51:49, 59:41, and 63:37, respectively). The results are discussed in terms of a theoretical study done for MFA using INDO calculations. Dissertation Discovery Company and University of Florida are dedicated to making scholarly works more discoverable and accessible throughout the world. This dissertation, "Stereochemical and Reactivity Studies of the 2 2], 2 4] and 1,3-dipolar Cycloadditions of Partially Fluorinated Allenes" by Gene Ellis Wicks, was obtained from University of Florida and is being sold with permission from the author. A digital copy of this work may also be found in the university's institutional repository, IR@UF. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation.
Автор: Matthew Wicks Название: Imaginative Projects Book ISBN: 0521668050 ISBN-13(EAN): 9780521668057 Издательство: Cambridge University Press Рейтинг: Цена: 2588.00 р. Наличие на складе: Нет в наличии.
Описание: Imaginative Projects is a photocopiable supplementary resource book for teachers of EFL learners aged 11-17. This book provides a bank of ten projects, on themes designed to capture the imagination of students and encourage them to use English naturally in groups to work on the project’s end product such as a poster, radio programme, or performance.
This flexible material is linked to coursebook topics and language areas. Eight of the projects consist of four single lesson 'mini projects' that can be used independently.
It offers step-by-step teaching notes, a cross-referenced map of the book and a mini-map at the start each project.
If you need a motivating, enjoyable alternative to supplement your coursebook, this is the book for you.
Описание: Abstract: Cycloadditions involving fluoroallenes are extremely useful mechanistic probes. Due to the high reactivity of these allenes and the small size of their fluorine substituents, cycloadditions of fluoroallenes are free from many of the ambiguities surrounding analogous studies by previous workers. Styrene and 1,1-difluoroallene, DFA, undergo clean reactions between 60o and 100oC to give good yields (approx. 60%) of two cylcloadducts: 2,2-difluoro-3-phenyl-1-methylenecyclobutane (major) and 3-phenyl-1-(difluoromethylene)cyclobutane (minor). Similar experiments comparing the reactions of p-nitro and p-methoxystyrene with the above results give relative reactivities of 2.1 and 1.3, respectively. The 2]2] cycloaddition of DFA with Z-β-deuteriostyrene gives the expected products in an 82:18 ratio with stereochemical ratios of 58:42 and 79:21, respectively, at 80oC. A mechanism involving two kinetically distinguishable diradicals is proposed to rationalize the results. The reaction of DFA with 1-cyanovinyl acetate, a "capto-dative" reagent is also studied and found to give results similar to the styrene reactions. N-Methyl, N-phenyl, and N-(2-naphthyl)-C-phenylnitrones undergo regiospecific C2-C3 dipolar cycloadditions with monofluoroallene, MFA, in nearly quantitative yields at 25oC. The average stereochemical ratio for the two 4-substituted isoxazolidines produced is 84:16 2% with the product from syn addition of MFA in excess. The stereochemical assignments of the products are made with the aid of difference nuclear Overhauser effect (NOE) experiments and an X-ray crystal structure. Extensive solvent and kinetic studies show that these are well-behaved second-order kinetic processes consistent with previously well-studied 1,3-dipolar cycloadditions. The reaction of MFA with diazomethane-d2 strongly favors the product from the syn addition (88:12 ratio), also. Consideration of transition-state dipole-dipole interactions and solvation phenomena show that the factors affecting the stereochemical outcome of all these 1,3-dipolar cycloadditions are extremely subtle. Finally, MFA undergoes Diels-Alder reactions with cyclopentadiene, butadiene, and furan to give a modest preference for the syn adduct (51:49, 59:41, and 63:37, respectively). The results are discussed in terms of a theoretical study done for MFA using INDO calculations. Dissertation Discovery Company and University of Florida are dedicated to making scholarly works more discoverable and accessible throughout the world. This dissertation, "Stereochemical and Reactivity Studies of the 2 2], 2 4] and 1,3-dipolar Cycloadditions of Partially Fluorinated Allenes" by Gene Ellis Wicks, was obtained from University of Florida and is being sold with permission from the author. A digital copy of this work may also be found in the university's institutional repository, IR@UF. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation.
Автор: Brandon Wicks Название: American Fallout ISBN: 1939650429 ISBN-13(EAN): 9781939650429 Издательство: Gazelle Book Services Рейтинг: Цена: 2992.00 р. Наличие на складе: Есть у поставщика Поставка под заказ.
Описание: For Avery Cullins--library archivist, former teenage runaway, and gay man from a small Southern town--"family" means a live-in boyfriend and a surly turtle. But when his father, a renowned nuclear physicist, commits suicide, Avery's decade-long estrangement from his mother, now hobbled following a stroke, comes to a skidding halt. With his boyfriend's help, Avery takes custody of his mother and the trio heads cross country in a rented U-Haul, back to an apartment in Cleveland and an uncertain future. Their journey soon becomes a pilgrimage into the past when Avery begins sifting through his mother's mementos. What emerges is a story of family, love, and loss as his parents made a home, lost a child, and tested the boundaries of marital love in the 1970s. Meanwhile, in today's uncertain social landscape, Avery must confront his own struggle with a mother who doesn't recognize him and a lover who seeks to claim him for his own.
Описание: This book is an invitation to come home to your authentic self in a world that is frequently mesmerized by spin, narcissism, fantasy, and exhibitionism. Psychology and classic wisdom literature have, in various ways, long recognized the value for simply becoming who you are (i.e., ordinariness). However, this call is becoming increasingly drowned out by the many other voices that emphasize publicity and image-making over authenticity and humility. Renowned therapist and author Robert Wicks has written The Tao of Ordinariness as a way of beginning to address these tendencies in contemporary society. In this new countercultural work, the strength and joy of exploring who you are - and proceeding to share yourself with others in a way that they too can reclaim themselves - is revisited from a range of vantage points. The author specifically reexamines themes of humility, simplicity, letting go, self-awareness, alonetime, resilience, and mentoring. In an era when people increasingly measure self-worth by external measures, such as the number of likes and views and followers on social media feeds (which have many individuals chasing impossible fantasies and living with a constant fear of missing out), Wicks offers a return to your authentic self.
Автор: Robert L. Wicks Название: Introduction to Existentialism ISBN: 1441192344 ISBN-13(EAN): 9781441192349 Издательство: Bloomsbury Academic Рейтинг: Цена: 4275.00 р. Наличие на складе: Есть у поставщика Поставка под заказ.
Описание: This textbook introduces you to existentialist philosophical theory and its cultural influence. The first part of the book offers an introductory overview of the 19th century historical roots of existentialist thought and chapters on all the key players: Kierkegaard, Nietzsche, Heidegger, Sartre, de Beauvoir, and Camus. The second part presents a thematic approach, with chapters on Christian and Jewish existentialism, existentialism in America, existential psychology and existentialism in the cinema. Ideal for undergraduate and classroom use, this engaging and accessible textbook includes pedagogical features, such as study questions, chapter summaries, key definitions and further reading.
Описание: The Everyday Blacksmith empowers hobbyist blacksmiths to make simple, practical projects for everyday use.
Автор: Wicks, Joe Название: Veggie lean in 15 ISBN: 1509856153 ISBN-13(EAN): 9781509856152 Издательство: Pan Macmillan Рейтинг: Цена: 2193.00 р. Наличие на складе: Есть у поставщика Поставка под заказ.
Описание: The first vegetarian cookbook from no.1 bestselling author of Lean in 15, Joe Wicks.
Автор: Sj Wicks Jared Название: Luther and His Spiritual Legacy ISBN: 1532602588 ISBN-13(EAN): 9781532602580 Издательство: Неизвестно Рейтинг: Цена: 3586.00 р. Наличие на складе: Есть у поставщика Поставка под заказ.
Описание: The emergence of home video in the 1980s marked the beginning of an era, as dozens of B movies were produced each year for the small screen, many becoming cult classics. Through numerous interviews with producers, directors, photographers and actors, this book sheds light on an overlooked corner of film history with behind-the-scenes stories of 28 low-budget favourites from the `80s.
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