19 resultados para Parsons, Lewis B. (Lewis Baldwin), 1818-1907.


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Ben N. Peach (1842-1926) was a well-known geologist whose work focused on the geological structure of Scotland, and in particular the Northwest Scottish Highlands and Southern Uplands. He formed a close working relationship with John Horne and the two colloborated on many works, most notably two memoirs of the Geological Survey of Great Britain, The Silurian Rocks of Britain (1899) and The Geological Structure of the North-West Highlands of Scotland (1907).

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This thesis describes the synthesis, structural studies, stoichiometric and catalytic reactivity of novel Mo(IV) imido hydride complexes (Cp)(ArN)Mo(H)(PMe3) (1) and (Tp )(ArN)Mo(H)(PMe3) (2). Both 1 and 2 catalyze hydrosilylation of a variety of carbonyls. Detailed kinetic and DFT studies found that 1 reacts by an unexpected associative mechanism, which does not involve Si-H addition either to the imido group or the metal. Despite 1 being a d2 complex, its reaction with PhSiH3 proceeds via a a-bond metathesis mechanism giving the silyl derivative (Cp )(ArN)Mo(SiH2Ph)(PMe3). In the presence of BPh3 reaction of 1 with PhSiH3 results in formation of (Cp)(ArN)Mo(SiH2Ph)(H)2 and (Cp)(ArN)Mo(SiH2Ph)2(H), the first examples ofMo(VI) silyl hydrides. AI: 1 : 1 reaction between 2, PhSiD3 and carbonyl substrate established that hydrosilylation is not accompanied by deuterium incorporation into the hydride position of the catalyst, thus ruling out the conventional mechanism based on carbonyl insertion carbonyl. As 2 is nomeactive to both the silane and ketone, the only mechanistic alternative we are left with is that the metal center activates the carbonyl as a Lewis acid. The analogous nonhydride mechanism was observed for the catalysis by (ArN)Mo(H)(CI)(PMe3), (Ph3P)2(I)(O)Re(H)(OSiMe2Ph) and (PPh3CuH)6. Complex 2 also catalyzes hydroboration of carbonyls and nitriles. We report the first case of metal-catalyzed hydroboration of nitriles as well as hydroboration of carbonyls at very mild conditions. Conversion of carbonyl functions can be performed with high selectivities in the presence of nitrile groups. This thesis also reports the first case of the HlH exchange between H2 and Si-H of silanes mediated by Lewis acids such as Mo(IV) , Re(V) , Cu(I) , Zn(II) complexes, B(C6Fs)3 and BPh3.

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Henry Haight Collier, was born in Howard, Steuben County, N. Y., November 28, 1818. His father, Richard Collier, was from Green County, in the same State. His grandfather, Isaac Collier, and his great-grandfather were originally from England. His mother, Mary Haight, was of Dutch origin. In 1835, Henry went to St. Catharines, where his elder brother, Richard Collier, resided. He spent two years at Grantham Academy, and then returned to Steuben County, to read law in Bath, with Edward Howell, and subsequently with Hammond and Campbell. Mr. Collier never opened a law office. He studied law for two years and in 1839 he went to Texas where he was connected with the State and Treasury Departments. In 1845 Mr. Collier returned to St. Catharines and opened a general store called St. Catharines Agricultural Works with his brother. The store remained open until May, 1877. He added the manufacturing of lumber in 1850, and manufacturing of agricultural implements in 1869. He built one of the first saw mills on the canal, on Lock No. 5, in St. Catharines. In July, 1877, he was appointed Collector of Customs. He became a Village Councilor for St. Paul’s Ward in 1859, and held that office from fifteen to twenty years. He was Deputy Reeve and member of the County Council for two terms. He was the Mayor of St. Catharines in 1872 and 1873. He was also Chairman of the Board of Water Commissioners of the city, during the time that the works were being built. He was a Justice of the Peace for twenty years or more. Mr. Collier was affiliated with the Reform Party and he was a Knight Templar in the Masonic fraternity and an Odd Fellow. He was also active in the Methodist Church. On June 1, 1858, he married Cornelia, daughter of Moses Cook, of "Westchester Place," St. Catharines, and had a daughter and son. Mary J. (married name: Mrs. Frank Camp) was a graduate of the Female Seminary at Hamilton, and Henry Herbert was a student in the University of Toronto. Henry H. Collier died on July 15, 1895 and is buried in Victoria Lawn Cemetery, St. Catharines, Ontario. Sources: www.accessgeneology.com "Historical Profiles from Victoria Lawn Cemetery" by Paul E. Lewis "Sincerely Lamented St. Catharines Obituaries 1817-1918" by Paul Hutchison

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The use of theory to understand and facilitate catalytic enantioselective organic transformations involving copper and hydrobenzoin derivatives is reported. Section A details the use of theory to predict, facilitate, and understand a copper promoted amino oxygenation reaction reported by Chemler et al. Using Density Functional Theory (DFT), employing the hybrid B3LYP functional and a LanL2DZ/6-31G(d) basis set, the mechanistic details were studied on a N-tosyl-o-allylaniline and a [alpha]-methyl-[gamma]-alkenyl sulfonamide substrate. The results suggest the N-C bond formation proceeds via a cisaminocupration, and not through a radical-type mechanism. Additionally, the origin of diastereoselection observed with [alpha]-methyl-[gamma]-alkenyl sulfonamide arises from avoidance of unfavourable steric interactions between the methyl substituent and the N -protecting group. Section B details the computationally guided, experimental investigation of two hydrobenzoin derivatives as ligands/ catalysts, as well as the attempted synthesis of a third hydrobenzoin derivative. The bis-boronic acid derived from hydrobenzoin was successful as a Lewis acid catalyst in the Bignielli reaction and the Conia ene reaction, but provided only racemic products. The chiral diol derived from hydrobenzoin successfully increased the rate of the addition of diethyl zinc to benzaldehyde in the presence of titanium tetraisopropoxide, however poor enantioinduction was obseverved. Notably, the observed reactivity was successfully predicted by theoretical calculations.