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Conformer determination of stabilized triphenyl phosphonium acyl ylides by infrared spectroscopy
(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 ...
Comparison of conformations of diesters of stabilized phosphonium ylides in solution and in the crystal
(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 ...
A common conformation of stabilized triphenyl phosphonium ylidic diesters with bulky alkoxy groups
(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, ...
Molecular structures and preferred conformations of stabilized keto diester phosphonium ylides
(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. ...
Infrared spectroscopy and ab initio computation in conformer determination of keto ester and diketo triphenylphosphonium ylides
(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 ...
Crystal structure and NMR spectra of 3-carboethoxy-3-triphenylphosphoranylidene-2-oxopropane triphenyl phosphonium bromide chloroform solvate
(SOCIEDAD CHILENA DE QUIMICA, 1998-12)
The crystal structure of C42H37O3P2Br has been determined by single crystal X-ray diffraction. The title compound is monoclinic, space group P2(1)/n (Nr. 14), with unit cell parameters a = 11.220(6), b = 14.345(10), c = ...
Cyano triphenyl phosphonium ylides stabilized by ester or keto groups: Computed conformations and crystal structures
(TAYLOR & FRANCIS LTD, 2007)
The mixed stabilized triphenyl phosphonium ylides Ph3P= C(CN)CO-R and Ph3P= C(CN)COOR, R= CH3, C2H5, CH(CH3)(2), 1a, c and 2a, b, respectively, have sharp H-1 and C-13 NMR signals, except for 2b in some conditions. Ab ...
Conformational differences in stabilized diketo and diester phosphonium ylides in a solid and in solution
(TAYLOR & FRANCIS LTD, 2007-01)
The diacyl ylid, 3-triphenylphosphoranylidene-2,4-pentanedione 2 can adopt conformations with one oxygen syn- and the other anti- to phosphorus 2a as in the crystal, or with both oxygens syn- to phosphorus 2b. In solution, ...
Estudio de reacciones de termólisis de sales de ésteres de trifenilfosfonio y de mono y diesteres de iluros de fósforo
(Universidad de Chile, 2014)
Se estudia la síntesis y el comportamiento térmico de sales de
trifenilfosfonio di sustituidas en el C α, con estructuras Ph3P+-CH(CO2R)-CO2R’ Xdonde
R= -CH3, y R’ = -CH2-CH3: 4 ; R= -CH2-CH3 y R’= -C(CH3)3 : 5 ; R= ...
4-Formilpirazoles y 3-formilpirazolo[1,5-a]pirimidinas como precursores de potenciales agentes antifúngicos fluorescentes
(Universidad de los AndesDoctorado en Ciencias - QuímicaFacultad de CienciasDepartamento de Química, 2022-05-25)
En este documento se presentan los resultados del trabajo de investigación de Doctorado en Ciencias-Química titulado "4-formilpirazoles y 3-formilpirazolo[1,5-a]pirimidinas como precursores de potenciales agentes antifúngicos ...