6231-03-4Relevant academic research and scientific papers
Alkali-metal ion catalysis and inhibition in nucleophilic displacement reaction of O-ethyl O-4-nitrophenyl phenylphosphonothioate with alkali-metal ethoxides
Um, Ik-Hwan,Kang, Ji-Sun,Shin, Minah
, p. 736 - 741 (2013)
A kinetic study on nucleophilic displacement reactions of O-ethyl O-4-nitrophenyl phenylphosphonothioate (an insecticide called EPN) with alkali-metal ethoxides (EtOM; M = Li, Na, K, and K/18-crown-6-ether) is reported. Dissection of pseudo-first-order rate constant (kobsd) into the second-order rate constants for the reaction of EPN with the dissociated EtO- (kEtO-) and ion-paired EtOM (kEtOM) has revealed that the reactivity increases in the order kEtOLi EtO EtONa EtOK EtOK/18-crown-6-ether, indicating that Li+ inhibits the reaction while the other M+ ions behave as a Lewis acid catalyst in the order Na+ + +. The contrasting M+ ion effects have been explained in terms of the hard and soft acids and bases (HSAB) principle, since EPN, as a polarizable P=S centered electrophile, would exert a weak interaction with Li+ (a hard acid) but a strong interaction with the 18C6-complexed K+ ion (a soft acid). M+ ions catalyze the current reaction by increasing the electrophilicity of the reaction center. EPN is less reactive than O-4-nitrophenyl diphenylphosphinothioate but is more reactive than O-4-nitrophenyl O,O-diethyl thiophosphate. Factors governing the reactivity of these P=S centered electrophiles are discussed.
Photocatalytic C-O Bond Cleavage of Alcohols Using Xanthate Salts
Nanjo, Takeshi,Matsugasako, Tatsuki,Maruo, Yuri,Takemoto, Yoshiji
supporting information, p. 359 - 363 (2022/01/15)
The homolytic cleavage of C-O bonds to afford alkyl radicals is an attractive yet challenging transformation in organic synthesis. Herein we describe a photocatalyzed deoxygenative C-C coupling reaction of xanthate salts, which can be easily prepared from the corresponding alcohols. The key to the success of this strategy is the low oxidation potential of the xanthate salt and the use of an appropriate phosphine to accelerate the desulfurative release of carbonyl sulfide.
Enantiopure O-substituted phenylphosphonothioic acids: Chiral recognition ability during salt crystallization and chiral recognition mechanism
Kobayashi, Yuka,Morisawa, Fumi,Saigo, Kazuhiko
, p. 606 - 615 (2007/10/03)
The chiral recognition ability of enantiopure O-methyl, O-ethyl, O-propyl, and O-phenyl phenylphosphonothioic acids (1a-d) for various kinds of racemic amines during salt crystallization and the chiral recognition mechanism were thoroughly investigated. T
Optical resolution reagent and manufacturing method of optically active amines that uses it
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Page/Page column 18, (2008/06/13)
PROBLEM TO BE SOLVEDTo provide an effective reagent for optical resolution which produce an optically active amines by resolving the (+/-)-amines and the method for producing the optically active amines characterized by using the same reagent. SOLUTION The O-alkylthiophosphoric acid represented as the following formula (1) is effective for the optical resolution of various amines.
A new hydrogen-bonding motif for chiral recognition in the diastereomeric salts of racemic 1-phenylethylamine derivatives with enantiopure O-ethyl phenylphosphonothioic acid
Kobayashi, Yuka,Morisawa, Fumi,Saigo, Kazuhiko
, p. 4227 - 4230 (2007/10/03)
(Chemical Equation Presented) An enantiopure phosphonothioic acid showed a unique and superior chiral recognition ability, arising from its P-stereogenicity, for racemic 1-phenylethylamine derivatives through diastereomeric crystallization. Spherical molecular clusters, associated by hydrogen bonds and CH/π interactions, aggregated with high symmetry in the less-soluble diastereomeric salts.
Reactivity of X3P compounds with elemental sulfur, carbon disulfide or both, to yield X3PS, X3RCS2 or X3P.Sn.CS2 adducts
Demarcq, Michel C.
, p. 307 - 320 (2007/10/03)
Kinetic constants k2 have been obtained for the reaction of sulfur with 25 PIII compounds in toluene or hexane. In the series PhnMe3-nP (n = 1-3) or PhnBu3-nP (n = 0-3), log k2 decreases linearly with Σχi (χi=Tolman's electronic parameter of each ligand on P), taken as a gauge for the donor strength of P. Dramatic deviations from additivity are observed for the series PhnP(OEt)3-n, PhnP(OEt)3-n, and BunP(OEt)3-n(n = 0-3); the deviation is smaller for PhnPCl3-n, and even smaller for PhnP(NEt2)3-n . The results are discussed in terms of P-coordination (PIV vs. PV), stability and geometry of the intermediate X3P.S8 or of the transition state leading to this adduct, emphasis being laid on the donor/acceptor character of the P site. A similar dependence on X governs the reactivity of X3P with S8, CS2 or both, to give X3PS, X3P.CS2 (binary red adduct) or X3P.Sn.CS2 (ternary yellow adduct) respectively; an explanation for this parallelism is proposed.
Kinetics and mechanism of the reaction of trico-ordinate phosphorus ompounds with octasulphur
Lloyd, John R.,Lowther, Nicholas,Zsabo, G.,Hall, C. Dennis
, p. 1813 - 1818 (2007/10/02)
Kinetic data and activation parameters are reported for the reactions of a series of phosphites, arylphosphonites, diarylphosphinites, and triarylphosphines with octasulphur (S8) in toluene as solvent.For the phosphites the data are explained in terms of changes in p-character of the Ione-pair orbital on phosphorus and inductive electron donation by the alkyl groups.The rates of reaction of series of arylphosphonites, diarylphosphonites, and triarylphosphones correlate with the Hammett ? constants to give ? values of -3.0, -3.0, and -2.5, respactively, and the results are discussed in terms of the Reactivity-Selectivity Principle and the biphilic mechanism or insertion of trico-ordinate phosphorus into ?-bonds.
O,O-Dialkyl Thiophosphoro- and O-Alkyl Phenylthiophosphono-cyanidates: Synthesis and Reactions
Das, Sushanta K.,Balasubrahmanyam, S. N.
, p. 254 - 256 (2007/10/02)
The title compounds (2a-d) have been prepared by the reactions of the corresponding chloridates (1a-d) with potassium cyanide in a two-phase system (dichloromethane-water) in the presence of cetyltrimethylammonium bromide.An unexpected facile conversion of these cyanidates (2a-d) into O,O,O-trialkyl thiophosphates (5a) or O,O-dialkyl phenyl thiophosphonates (5b) has been observed in the presence of aqueous alcoholic potassium hydroxide.
