Browsing by Author "70abb195-512e-49e2-97ec-c7f25a67b539"
Now showing items 1-18 of 18
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A common conformation of stabilized triphenyl phosphonium ylidic diesters with bulky alkoxy groups Castañeda, Fernando; Silva, Paul; Garland, María Teresa; Shirazi, Ata; Bunton, Clifford A. (2009)The phosphonium ylidic diesters, methyl and ethyl isopropyl and, methyl and ethyl t-butyl triphenylphosphoranylidene malonates, 1a,b and 2a,b, respectively, have the syn-anti conformation in solution, as in the crystal, ...
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Aromatic nucleophilic substitution in nucleophilic surfactants. Comparison with alkoxide reactions Bunton, Clifford A.; Díaz, Simon (1976)The reactions of 2,4-dinitrochloro- and fluorobenzene (DNC and DNF) with the alkoxide ions of choline, propargyl alcohol, and 2,2,2-trifluoroethanol give ether intermediates which react readily with hydroxide ion. The ...
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Castañeda, Fernando; Silva, Paul; Garland, María Teresa; Shirazi, Ata; Bunton, Clifford A. (2009)Computed bond lengths and angles of methyl ethyl and dimethyl triphenyl phosphonium ylidic diesters, 1b, c, respectively, are similar to those in the crystal, as for the diethyl ester, 1a, where both acyl oxygens are anti ...
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Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel; Parada Aliste, José; Blasko, Andrei; Bunton, Clifford A. (Sociedad Chilena de Química, 1997)D-β-Mannosamine reacts with cobalt(III) bis-phenanthroline to form a single 1:1 complex with the ∆ configuration at Co(III) which can be isolated as the stable triiodide salt.
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Chayet, Liliana; Rojas, M. Cecilia; Cori, Osvaldo; Bunton, Clifford A.; McKenzie, Don C. (1984)Kinetic analysis of the nonenzymic solvolysis of neryl and geranyl pyrophosphate (NPP and GPP, respectively) showed that the dissociation constants of the bis-metallic complexes with Mg2+ and Mn2+ were larger for NPP than ...
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Castañeda Magliona, Fernando; Silva, Paul; Acuña, Cristina; Garland, María Teresa; Bunton, Clifford A. (2013)In ylidic triphenylphosphonium carboxylic esters the ester oxygen can be oriented towards (syn) or away (anti) from phosphorus, but except for small ylidic ester groups, e.g., Me, the anti conformer is dominant. With ...
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Bunton, Clifford A.; Silva, Paul; Castañeda, Fernando (2009)Stretching frequencies of acyl groups of stabilized triphenyl phosphonium ylides with ester, keto or cyano groups depend in part on the orientations of the acyl groups, syn or anti, with respect to phosphorus. Frequencies ...
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Castãeda, Fernando; Jullian Matthaei, Carolina; Bunton, Clifford A.; Garland, María Teresa; Baggio, Ricardo (2007)Hydrogen bonding and crystal packing play major roles in determining the conformations of ethyl methyl 2-(triphenyl-phospho-ranyl-idene)malonate, Ph3P=C(CO2CH3)CO2CH2CH3 or C24H23O4P, (I), and dimethyl 2-(triphenyl-phosphor- ...
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Alarcón, Maritza; Cori, Osvaldo; Rojas, M. Cecilia; Pavez, Hernán; Bacaloglu, Radu; Bunton, Clifford A. (1992)Hydrolysis of geranyl diphosphate (GPP) at pH 7 in water gives largely linalool (LOH) + geraniol (GOH) in the ratio of 3:1. Added N−3 generates mixed acylic allylic azides and increases the LOH GOH ratio to 15:1 in 2 M ...
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Bunton, Clifford A.; Sepulveda, Luis (1979)The transfer free energies of a series of substituted phenols and phenoxide ions from water to micelles of cetyltrimethylammonium bromide (CTABr) have been measured at high and low pH. The contribution of each methylene ...
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Bunton, Clifford A.; Castañeda Magliona, Fernando (Elsevier, 2009)For stabilized triphenylphosphonium keto ester ylides acyl stretching frequencies of the anti ester group from HF/6-31G(d) calculations fit experimental values with Scale Factor, SF = 0.866, as estimated earlier for the ...
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Bunton, Clifford A.; Sepúlveda, Luis (Laser Pages Publ., 1979)Cationic micelles of hexadecyltrimethyl ammonium bromide (CTABr) increase the rate of dephosphorylation of p‐nitrophenyldiphenyl phosphate (PNPDPP) by aryloxide ions by factors of almost 104. The rate‐surfactant profiles ...
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Bunton, Clifford A.; Diaz, Simon; Hellyer, James M.; Ihara, Yasuji; Ionescu, Lavinel G. (1975)The spontaneous hydrolysis of 2,4-dinitrophenyl phosphate dianion (I) is catalyzed by cationic micelles of the choline-derived surfactant (II, n-C16H33N+Me2CH2CH2OHBr-), but this surfactant is no more effective than ...
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Parada Aliste, José; Bunel Torrealba, Sergio; Moraga, Exequiel; Ibarra, Carmen; Gillitt, Nicholas D.; Bunton, Clifford A. (2001)Mixed complexes of bis-phenanthroline cobalt(III) and α-D-galactose or β-D- or L-arabinose are identified in aqueous solution from their 1H NMR and circular dichroism (CD) spectra. Galactose forms only the Δ-complex, but ...
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Castañeda, Fernando; Silva, Paul; Garland, María Teresa; Shirazi, Ata; Bunton, Clifford A. (2011)Triphenylphosphonium ylidic keto diesters with a nonylidic ester group, Ph3PC(CO2CH2CH3)COCO 2CH2CH3, 1, and Ph3PC(CO 2CH2CH3)COCH2CO2CH 2CH3, 2, have the keto group syn and the ylidic ester acyl group anti to phosphorus. ...
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Cori Moully, Osvaldo; Chayet Timmiling, Liliana; Perez Roepke, Luz Maria; Bunton, Clifford A.; Hachey, David (American Chemical Society, 1986)Acid-catalyzed conversion of linalool into geraniol, nerol, and a-terpineol is slower than the corresponding reactions of geraniol and nerol, because the tertiary linalyl carbocation reverts to linalool rather than going ...
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Parada Aliste, José; Ibarra, Carmen; Gillitt, N. D.; Bunton, Clifford A. (PERGAMON-ELSEVIER SCIENCE LTD, 2005-06-28)The title compound (sucrose Co(phen)(2)) is a dication with the Delta-configuration at Co(III) and ligation through O-2(g) and OH-1(f). Earlier geometrical optimization with semi-empirical PM3(tm) parameters had fitted ...
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Bunel Torrealba, Sergio; Ibarra, Carmen; Calvo Pérez, Víctor; Blasko, Andrei; Bunton, Clifford A.; Keder, N. L. (PERGAMON-ELSEVIER SCIENCE LTD, 1991)The crystal structure of the title compound has been determined from single crystal X-ray diffraction data. There is little angle strain in the complex which has two carboxylate ions and one alkoxide ion bound to cobalt(III). ...