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Synthesis and Characterisation of Phosphonium Ylides

Ylides containing fluorine atoms are of obvious utility, considering the importance of fluorine-containing compounds and materials. Kolodiazhnyi and Schmutzler have reviewed the synthesis, properties and applications of ylides [Pg.293]

Other new ylides that have been reported recently include (53), which is useful for the conversion of aldehydes into Y,b-unsaturated allyl p-ketoesters, and (54), [Pg.296]

The triflic acid-promoted hydrolysis of bis-triphenylphosphonio-isophos-phindolide cation (38) has been followed using NMR spectroscopy. No evidence was found for direct phosphorus protonation or alkylation which had previously been postulated. [Pg.163]

Hanamoto and co-workers have published a detailed report on the synthesis and reactivity of a-fluorovinylphosphonium salt (39), which they had first described in a previous communication. Ylides derived from (39) have been [Pg.163]

Cheng and co-workers have reported a unique method for the synthesis of fullerene derivatives of ylides (45) from the reaction of C o with tertiary phosphines and electron deficient acetylenes. All four new ylides show temperature dependent NMR spectra that can be rationalised on the basis of the interchange between two E, Z isomers. The structure of compound (45a) was determined crystallographically. [Pg.163]

Other ylides which have been reported include (46), which undergoes [Pg.163]


The Synthesis and Characterisation of Phosphonium Ylides. - Bertrand and co-workers have reported the instantaneous quantitative formation of phosphorus ylides (15) when stable phosphanylcarbenes are treated with phosphines (Scheme 1). Ylides (15) are very readily oxidised by atmospheric... [Pg.160]

Synthesis and Characterisation of Phosphonium Ylides. - We start this section with a phosphanylidene-o -phosphorane (14) which, although not strictly an ylide, has a P-P bond which displays many of the properties of more conventional phosphonium ylides. A crystal structure of (14) revealed a P-P bond length of 2.084(2) A, which is similar to those found in other phos-phanylidene-o( -phosphoranes and is certainly shorter than a typical P-P single bond ca. 2.22 A), indicative of multiple bond character. Compound (14) undergoes reactions with electrophiles (Scheme 1) which demonstrate its nucleophilic... [Pg.291]


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