35000-37-4Relevant articles and documents
Thermal decomposition of triphenylphosphonium alkyl ester salts
Castaneda, Fernando,Aliaga, Christian,Acuna, Cristina,Silva, Paul,Bunton, Clifford A.
experimental part, p. 1188 - 1208 (2009/04/16)
In thermolyses of molten triphenylphosphonium alkyl ester bromides and chlorides, alkyl = methyl, ethyl, isopropyl, at 130 and 225°C, initial attack of the halide ion on the methyl group gives the methyl halide and ylid 1, Ph3P = CH2, which can be methylated, or is protonated by the phosphonium salt with transylidation giving Ph3P+-CH3X-, X = Br, Cl. The initial reactions of the ethyl or isopropyl esters are with the halide ion, X-, as a base giving ylid, 1, which can be protonated by HX or by transylidation. The t-butyl ester generates Ph3P+-CH3X-but no products of transylidation. The first-formed ylid1, can be trapped by reactive alkyl and acyl halides, and the transient ylidic esters decompose thermally to triphenyl phosphine oxide, Ph3P = O, react further with unreacted phosphonium ester, or are trapped by added aldehyde in a Wittig reaction. The final product compositions are affected by a decrease in pressure, due to escape of volatile intermediates, and by replacement of the X- halide ion by the less nucleophilic and basic tosylate ion. Reactions under reflux, in solution in chloroform, or in suspension in benzene, are similar to those of the molten salts, but yields are generally lower at the lower temperatures. Copyright Taylor & Francis Group, LLC.
Flash vacuum pyrolysis of stabilised phosphorus ylides. Part 15. Generation of alkoxycarbonyl(sulfenyl)carbenes and their intramolecular insertion to give alkenyl sulfides
Aitken, R. Alan,Armstrong, Jill M.,Drysdale, Martin J.,Ross, Fiona C.,Ryan, Bruce M.
, p. 593 - 604 (2007/10/03)
A range of 18 alkoxycarbonyl sulfinyl phosphorus ylides 9 have been prepared and their behaviour upon flash vacuum pyrolysis (FVP) at 600 deg C examined. For R1 = H, Me and Et they lose Ph3PO and in some cases Ph3P to give mixtures of products including the alkenyl sulfides 10, the sulfides 11, the disulfides 12 and the thioesters 14. The alkenyl sulfides 10 most likely arise from intramolecular insertion of the alkoxycarbonyl sulfenyl carbenes resulting from loss off Ph3PO to produce β-lactones which then lose CO2 and this is supported by the results from 13C labelled ylides. Possible mechanisms for the formation of 11 and 14 are also presented and the feasibility of various steps has been examined by preparation and pyrolysis of the proposed intermediates. In contrast, pyrolysis of the ylides 9 where R1 = Ph and the tert-butoxycarbonyl ylides 30 leads mainly to complete fragmentation with loss of Ph3PO and benzyl alcohol or 2-methylpropan-2-ol and does not give any useful sulfur-containing products. Four alkoxy-carbonyl sulfonyl diazo compounds 33 have been prepared and in three cases they give the alkenyl sulfones 34 upon FVP at 400 deg C, probably by an intramolecular insertion and decarboxylation process analogous to the formation of 10 from 9. On the other hand the alkoxycarbonyl carbenes produced by FVP of the amino acid-derived diazo compounds 35 undergo alternative proocesses with no sign of β-lactone formation. Fully assigned 13C NMR data are presented for 13 of the ylides.
SYNTHESIS AND CHARACTERIZATION OF PYRROLINONECARBOXYLATES FORMED BY REACTION OF VICINAL TRICARBONYL DERIVATIVES WITH ALDEHYDE SCHIFF BASES
Wasserman, Harry H.,Ennis, David S.,Vu, Chi B.,Schulte, Gayle,Munk, Morton E.,et al.
, p. 975 - 995 (2007/10/02)
A series of vicinal tricarbonyl derivatives undergo reaction with aldehyde Schiff bases forming pyrrolinone derivatives by benzilic acid-related rearrangements.The structures were established by X-ray analyses and, independently by the SESAMI NMR-based computer program.
SYNTHESIS OF 1-SUBSTITUTED (S)-4-ACETOXY-1-PENTEN-3-ONES USING (S)-LACTIC ACID AS A CHIRAL SOURCE AND THEIR SYNTHETIC REACTIONS
Hiyama, Tamejiro,Kobayashi, Kumi,Fujita, Makoto
, p. 4959 - 4962 (2007/10/02)
Ylide reaction of (S)-3-acetoxy-1-triphenylphosphoranylidene-2-butanone, derived from (S)-lactic acid, with aldehydes gives 1-substituted (S)-4-acetoxy-1-penten-3-one derivatives, which are shown to be transformed into useful chiral compouds by stereosele
