929 resultados para Nucleophilic additions
Resumo:
A number of 2-chlorobenzophenones, containing electron releasing groups (e.g. hydroxy, thiomethoxy and methoxy) in the 4' - position, were prepared by the Friess rearrangement, or the Friedel-Crafts reaction. These ketones, when treated with potassamide in liquid ammonia, underwent partial Haller-Bauer scission, unlike 2-chlorobenzophenone which is known to undergo complete scission. Under similar conditions 4-nitrobenzophenone also underwent partial scission, but the main reaction in this case was nucleophilic amination of the nitro containing ring. This amination reaction was shown not to be a useful general reaction for aromatic nitro compounds. 3-Methylxanthone was then prepared by treatment of 2- and 3- chloro-2'-hydroxy-5'-methylbenzophenone with . little, if any, attendant scission. The corresponding 2fluoro- compound also gave the xanthone, but as the 3-fluoro compound did not, it was concluded that the 2-fluoro compound reacted through a nucleophilic substitution mechanism, rather than the benzyne mechanism invoked for the chloro and bromo compounds. 3-Methylthioxanthone was synthesised by treatment of methyl 4-tolyl sulphide and 2-chlorobenzoyl chloride with aluminum chloride in carbon disu1phide, followed.by heating. This compound was also prepared by treatment of 3-chloro-2'thiomethoxy- 5'-methylbenzophenone with potassamide in liquid ammonia.
Resumo:
Decomposition and side reactions of, and the synthetic use of, pentafluorophenylmagnesium bromide and pentafluorophenyllithium have been investigated using G,C9/M.S, techniques• Their reactions with reagents such as CgF^X (X - H, F, CI, Br, 1), C6F4X2 (X - H, CI)f C6F3C13, C6H6. (CgX5)3P (X = H, F), (C6X5)3P=0 (X = H, F), (CgX5)Si (CH3)3 (X = H, F) and (CH0K SiCl , n = 1,2, in ether or ether/n-hexane were studied• In addition to the principal reaction of synthetic use, namely the replacement of a halogen by a pentafluorophenyl group, two types of side reactions were observed* These were (i) intermolecular loss of LiF via a nucleophilic substitution, and (ii) intramolecular loss of LiF, followed by the addition of either inorganic salts such as lithium or magnesium halides, or organometal compounds such as organolithium or organo-Grigaard* G.C«/M.S. techniques were routinely employed to study complicated reaction mixtures. Although mass spectrometry alone has disadvantages for the identification of isomers, deduction of the most probable pathway often helps overcome this problem.
Resumo:
This thesis explores the comparison utilitarianism and Buddhist ethics as they can be applied to animal research. It begins by examining some of the general discussions surrounding the use of animals in research. The historical views on the moral status of animals, the debate surrounding their use in animals, as well as the current 3R paradigm and its application in Canadian research are explored. The thesis then moves on to expound the moral system of utilitarianism as put forth by Jeremy Bentham and John Stuart Mill, as well as contemporary additions to the system. It also looks at the basics of Buddhist ethics well distinguishing the Mahayana from the Therevada. Three case studies in animal research are used to explore how both systems can be applied to animal research. It then offers a comparison as to how both ethical systems function within the field of animal research and explores the implications in their application on its practice.
Resumo:
The menu, with wine list from the Ladies’ and Gentlemens’ Ordinary of the Clifton House hotel in Niagara Falls, Ont. Also includes handwritten additions or alterations to the printed menu. The proprietors of the hotel were D.H. Bromley & Co. The Clifton House hotel was built in 1833 and destroyed by fire in 1896. It was known as the finest hotel on the Canadian side of the falls. Oakes Garden Theatre marks its location today.
Resumo:
Stocks added to (deleted from) the Russell 2000 and the S&P 600 indexes experience positive (negative) abnormal returns following the announcement. However, researchers disagree on whether these abnormal returns are permanent or temporary and offer competing explanations. I address this controversy by examining market reactions for firms that are added to or deleted from the FTSE Small Cap index (the main testing sample) and the S&P/TSX SmallCap index (the comparison sample). For the main testing sample, all stocks except pure additions, experience a permanent price change that is accompanied by a permanent change in liquidity. However, for the comparison sample, abnormal returns over the announcement period fully reverted within 30 days. In further examination of stock liquidity for the main testing sample, sample stocks experience permanent change in liquidity. Taken together, the observed results support the price pressure and liquidity hypotheses.
Resumo:
Newly repainted signage on the Old Student Union, Chapman College, Orange, California; part of a campus renewal project in 1973. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Lounge area of the old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Lounge area of the old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Old Student Union patio, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Snack bar inside the old Student Union, Chapman College, Orange, California in the 1970s. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Patio area of old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Patio area of the old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Hungrey Panther entrance at the old Student Union, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.
Resumo:
Old Student Union patio remodel in progress, Chapman College, Orange, California. Originally the manual arts building and bus repair garage for Orange Union High School. Building annex additions through 1975 increased the size to 19,680 sq. ft. Used as a student union by Chapman College. In 1996 the building became the Cecil B. DeMille Hall, housing the Film and TV department.