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On the reactivity of alpha-(triphenylphosphoranylidene)-benzylphenylketene with nitrogen compounds. Synthetic and mechanistic implications
(Soc Brasileira QuimicaSao PauloBrasil, 2002)
Preferred conformations of stabilized phosphorus ylides
(TAYLOR & FRANCIS LTD, 2003-09)
The stabilized phosphorus ylides, Ph3P=C(CO.R')CO.OR, 1, R=Et, R' =CH2P+Ph3; 2, R=R'=Me; 3, R=Et, R'=Me; 4, R=Pr-i; R'=Me, 5, R=Bu-t; R'=Me, adopt a near planar conformation in the crystal which allows extensive electronic ...
Conformations of monoylidic diester triphenylphosphonium ylides
(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 ...
On the Reactivity of α-(Triphenylphosphoranylidene)-benzylphenylketene with Nitrogen Compounds. Synthetic and Mechanistic Implications
(Brasil, 2002)
The reactivity of α-(triphenylphosphoranylidene)-benzylphenylketene, a stabilized phosphorus
ylide derived from diphenylcyclopropenone, toward nitrogen compounds was investigated.
Particularly, the reaction of diethyl ...
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 ...
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 ...
Cyano-stabilized triphenylphosphonium ylids
(BLACKWELL PUBLISHING, 2007-01)
Crystalline cyano-stabilized triphenylphosphonium ylids with keto or ester groups give rise to an extended electronic delocalization. In methyl 2-cyano-2-(trimethylphosphonio)-ethenoate, Ph3P=C(CN)CO2CH3 or C22H18NO2P, ...
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. ...