3582-83-0Relevant academic research and scientific papers
Synthesis of α,β-Unsaturated Phosphine Sulfides
Chen, Jin-Xiang,Jia, Xue-Shun,Wang, Xian-Liang,Yin, Liang
, p. 141 - 149 (2019/12/26)
α,β-Unsaturated phosphine sulfides may exhibit different reactivity from α,β-unsaturated phosphine oxides toward nucleophilic addition and thus may find new applications in copper(I)-catalyzed asymmetric reactions. Herein, various α,β-unsaturated phosphine sulfides were prepared in moderate to excellent yields from the parent α,β-unsaturated phosphine oxides with Lawesson's reagent. The reaction enjoys a broad substrate scope and tolerates a variety of functional groups.
Mechanistic Investigation of Well-Defined Cobalt Catalyzed Formal E-Selective Hydrophosphination of Alkynes
Rajpurohit, Jitendrasingh,Kumar, Pardeep,Shukla, Pragya,Shanmugam, Muralidharan,Shanmugam, Maheswaran
, p. 2297 - 2304 (2018/07/31)
A formal E-selective hydrophosphination of terminal and internal alkynes catalyzed by a well-defined [Co(PMe3)4] (A) complex is achieved under mild conditions in good-to-excellent yield. The reaction does not require any additives and/or external base for an efficient hydrophosphination reaction. The reaction provided excellent scope and good functional tolerance. Detailed spectroscopic analysis (NMR, EPR, and UV-vis) revealed that the low valent cobalt(0) complex undergoes oxidative addition with diphenylphosphine, followed by hydrometalation with alkyne, and subsequent reductive elimination led to the expected product. The detailed spectroscopic analyses along with the isotopic labeled experiments facilitate to intercept the active intermediates that are involved in the catalytic cycle, which are detailed. It was revealed that the suprafacial (vide infra) delivery of H and phosphorus to π-alkynes in a syn-fashion led to formal E-vinyl phosphine.
nBuLi-mediated hydrophosphination: A simple route to valuable organophosphorus compounds
Perrier, Arnaud,Comte, Virginie,Moise, Claude,Richard, Philippe,Le Gendre, Pierre
experimental part, p. 1562 - 1568 (2010/06/15)
A straightforward synthesis of homoallyl- and allylphosphanes has been developed using nBuLi-mediated hydrophosphination of conjugated dienes. In all the cases the phosphorus atom of the reacting phosphane attacked the sterically less demanding side of the diene exclusively. In addition, high regioselectivities towards 1,2- or 1,4-addition products were observed depending on the nature of the dienes. This hydrophosphination reaction was extended to a variety of substrates such as styrene derivatives, alkynes and 1,3,5-cycloheptatriene. The structures of three hydrophosphination products were confirmed by X-ray diffraction studies.
Cobalt-catalyzed syn hydrophosphination of alkynes
Ohmiya, Hirohisa,Yorimitsu, Hideki,Oshima, Koichiro
, p. 2368 - 2370 (2007/10/03)
Treatment of terminal and internal alkynes with diphenylphosphane in the presence of catalytic amounts of a base and cobalt (II) acetylacetonate affords, with perfect and universal syn selectivity, the (E)-alkenyldiphenylphosphane derivatives in good yiel
Reactivity of lithium diphenylphosphonium diylides towards phosphorus electrophiles: Synthesis of α,β-unsaturated phosphorus compounds
Taillefer, Marc,Cristau, Henri Jean,Fruchier, Alain,Vicente, Virginie
, p. 307 - 315 (2007/10/03)
The study of the reactivity of non-stabilized, semi-stabilized and stabilized lithium diphenylphosphonium diylides 1-4 towards Ph2PCl, allowed the synthesis of various α,β-unsaturated phosphines 13-14, via the intermediate formation of the corresponding functionalized monoylides 9-10 and their in situ reaction with carbonyl compounds. In many cases, the reaction is Z-stereoselective and the created double bond can be di- or also trisubstituted. The precise 1H-NMR study of the phosphines 13a-d and the X-ray analysis of 13a (Z isomer) allowed us to assign without ambiguity the stereochemistry of these compounds and to solve a 1H-NMR question. Contrary to reported results in the literature for 13a, we have shown that for the double bond of this phosphine, there is no exception to the general rule 3JHH(trans) > 3JHH(cis). The extension of this reactivity study to other phosphorus electrophiles such as Ph2P(O)Cl, Ph2P(S)Cl and (EtO)2P(O)Cl allowed, as preliminary results, the E-stereoselective synthesis of styrylphosphine oxide and sulfide and diethyl styrylphosphonate.
Stereo-controlled synthesis of styrylphosphines and their oxides or sulfides using phosphonium diylides
Taillefer,Cristau
, p. 7857 - 7860 (2007/10/03)
Lithium dimethyldiphenylphosphonium diylide reacts with electrophiles such as Ph2PCl, Ph2P(O)Cl or Ph2P(S)Cl to give monoylide intermediates allowing by reaction with benzaldehyde the synthesis of the styrylphosphines or the corresponding oxides or sulfides. This efficient one-pot method permits at choice the selective synthesis of each isomer Z or E and corroborates further the isomeric identification of the styrylphosphines.
Dual Radical/Polar Pudovik Reaction: Application Field of New Activation Methods
Semenzin, Delphine,Etemad-Moghadam, Guita,Albouy, Dominique,Diallo, Ousmane,Koenig, Max
, p. 2414 - 2422 (2007/10/03)
The Pudovik reaction (addition of organophosphorus compounds containing a labile P-H bond with alkenes and alkynes) can progess via a radical or (and) ionic mechanism. A comparative and systematic study including various reagents and different activation methods (heating, photochemical or ultrasonic irradiation, and dry medium supported reactions) is presented. Photolysis is the most efficient method for the radical processes, but in a few examples, ultrasonic irradiation can be more appropriate since the reaction time is shorter and ultrasound did not induce side-reactions (in particular Z/E isomerization). Dry medium process on basic solid support is the best anionic activation (yield, time, selectivity, purification facilities). Ultrasound, by its mechanical effects, can contribute to increase yield compared to the classical thermal method under these basic conditions. All the activation methods are efficient whatever the unsaturated substrates for the phosphine reactivity, whereas the appropriate activation method is exclusively determined by the nature of the unsaturated system for the thiophosphine (or phosphine oxide) reactivity.
Reactivity of carbanions stabilized by two alpha phosphorus groups
Goli,Grim
, p. 3631 - 3634 (2007/10/02)
The stabilized anion {[Ph2P(S)]2CH}- with lithium as counter cation 1a reacts with formaldehyde or benzaldehyde to give vinylidene phosphine sulfides [Ph2P(S)]2C=CHR, where R is H or Ph, respectively
Preparation of β-Substituted trans-Ethylene Diphenylphosphines and Sulphides by P(O) and P(S)-activated Olefination
Gloyna, Dieter
, p. 360 - 366 (2007/10/02)
Methylene bis-diphenylphosphine monoxide (3c) in toluene reacts regiospecifically and stereoselectively with aldehydes in the presence of potassium tert-butoxide to β-substituted trans-ethylene diphenylphosphines 6, which can be oxidized to the sulphides 2 by sulphur in acetone.These sulphides 2 are to be obtained also directly from methylene bis-diphenylphosphine oxide sulphide 3b and methylene bis-diphenylphosphine disulphide 3d, respectively, under the same olefination conditions.But the yields are smaller and the purification of the raw products is much more difficult, if 3d is used.
