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1.
Santana MD García G Lozano AA López G Tudela J Pérez J García L Lezama L Rojo T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(7):1738-1746
The bis(phosphatediester)-bridged complexes [[Ni([12]aneN(3))(mu-O(2)P(OR)(2))](2)](PF(6))(2) [[12]aneN(3)=Me(3)[12]aneN(3), 2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene; R=Me (1), Bu (2), Ph (3), Ph-4-NO(2) (4); [12]aneN(3)=Me(4)[12]aneN(3), 2,4,4,9-tetramethyl-1,5,9-triazacyclododec-1-ene; R=Me (5), Bu (6), Ph (7), Ph-4-NO(2) (8)] were prepared by hydrolysis of the phosphate triester with the hydroxo complex [[Ni([12]aneN(3))(mu-OH)](2)](PF(6))(2) or by acid-base reaction of the dialkyl or diaryl phosphoric acid and the above hydroxo complex. The acid-base reaction was also used to synthesise the phosphinate-bridged complexes [[Ni([12]aneN(3))(mu-O(2)PR(2))](2)](PF(6))(2) [[12]aneN(3)=Me(3)[12]aneN(3), R=Me (9), Ph (10); [12]aneN(3)=Me(4)[12]aneN(3), R=Me (11), Ph (12)]. The molecular structures of complexes 2, 3 and 12 were established by single crystal X-ray diffraction studies. The eight-membered rings defined by the nickel atoms and the bridging ligands show distorted twist-boat, chair and boat-boat conformations in 2, 3 and 12, respectively. The experimental susceptibility data for compounds 2, 3 and 12 were fitted by least-squares methods to the analytical expression given by Ginsberg. The best fit was obtained with values of J=-0.11 cm(-1), D=-9.5 cm(-1) and g=2.20 for 2; J=-0.97 cm(-1), D=-9.3 cm(-1) and g=2.21 for 3; and J=-0.14 cm(-1), D=-11.9 cm(-1) and g=2.195 for 12. The magnetic-exchange pathways must involve the phosphate/phosphinate bridges, because these favour antiferromagnetic interactions. The observation of a higher exchange parameter for compound 3 is a consequence of a favourable disposition of the O-P-O bridges. The kinetics for the hydrolysis of TNP (tris(4-nitrophenyl)phosphate) with the dinuclear nickel(II) hydroxo complex [[Ni(Me(3)[12]aneN(3))(mu-OH)](2)](PF(6))(2) was studied by UV-visible spectroscopy. The proposed mechanism for TNP-promoted hydrolysis can be described as one-substrate/two-product, and can be fitted to a Michaelis-Menten equation. 相似文献
2.
Phosphinic and phosphonic acids are useful intermediates and biologically active compounds which may be prepared from their esters, phosphinates and phosphonates, respectively, by hydrolysis or dealkylation. The hydrolysis may take place both under acidic and basic conditions, but the C-O bond may also be cleaved by trimethylsilyl halides. The hydrolysis of P-esters is a challenging task because, in most cases, the optimized reaction conditions have not yet been explored. Despite the importance of the hydrolysis of P-esters, this field has not yet been fully surveyed. In order to fill this gap, examples of acidic and alkaline hydrolysis, as well as the dealkylation of phosphinates and phosphonates, are summarized in this review. 相似文献
3.
Wei Wang Dr. Lisa Sturm David Sommer Prof. Dr. Iris Oppel Prof. Dr. Markus Albrecht 《欧洲无机化学杂志》2023,26(21):e202300075
Phosphinate and phosphane substituted hierarchical helicates have been prepared, and the phosphinate derivatives could be characterized in the crystal. The helicate with phosphane substituents was submitted to an orientating study on catalysis, showing its potential to act as chelating ligand for the generation of active rhodium-based hydrogenation catalysts. 相似文献
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Efficient Asymmetric Hydrogenation of α‐Acetamidocinnamates through a Simple,Readily Available Monodentate Chiral H‐Phosphinate
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Dr. Xiang‐Bo Wang Dr. Midori Goto Dr. Li‐Biao Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3631-3635
An air‐stable, simple (RP)‐mentylbenzylphosphinate, readily available in large quantities, can efficiently induce the rhodium‐catalyzed asymmetric hydrogenation of α‐acetamidocinnamates with high enantioselectivity (up to 99.6 % ee). Intramolecular hydrogen bonding plays an important role in this asymmetric induction. 相似文献
7.
Chemoselective Activation of Diethyl Phosphonates: Modular Synthesis of Biologically Relevant Phosphonylated Scaffolds
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Dr. Pauline Adler Dr. Amandine Pons Dr. Jing Li Jörg Heider Bogdan R. Brutiu Prof. Dr. Nuno Maulide 《Angewandte Chemie (International ed. in English)》2018,57(40):13330-13334
Phosphonates have garnered considerable attention for years owing to both their singular biological properties and their synthetic potential. State‐of‐the‐art methods for the preparation of mixed phosphonates, phosphonamidates, phosphonothioates, and phosphinates rely on harsh and poorly selective reaction conditions. We report herein a mild method for the modular preparation of phosphonylated derivatives, several of which exhibit interesting biological activities, that is based on chemoselective activation with triflic anhydride. This procedure enables flexible and even iterative substitution with a broad range of O, S, N, and C nucleophiles. 相似文献
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Akari Kawajiri Dr. Taro Udagawa Prof.Dr. Mao Minoura Prof.Dr. Toshiaki Murai 《ChemistryOpen》2022,11(11)
The substitution reaction of phosphinates with a binaphthyloxy group at the phosphorus atom with lithium alkoxides proceeded with good to high efficiencies to give P‐chirogenic phosphinates with a high enantiomeric ratio. As alcohols, primary, secondary, and tertiary alcohols could be used, and the use of tert‐butyl alcohol yielded the products with a higher enantiomeric ratio. A substrate with two different alkyl groups on the phosphorus atom could also participate in the substitution reaction to give the corresponding products in good yields with excellent selectivity. The molecular structures of one of the substrates and the corresponding products, determined by X‐ray analyses, proved that the substitution reaction at the phosphorus atom proceeded with inversion of the absolute configuration. The usefulness of the reaction was demonstrated by using it to prepare a drug candidate for Duchenne muscular dystrophy. Finally, thionation of the resulting phosphinates was carried out to form P‐chirogenic phosphinothioates. 相似文献
10.
1-Hydroxy-3-phospholene oxides (1 and 3) and phenyl-H-phosphinic acid (6) are converted to the corresponding phosphinic esters (2, 4, and 7, respectively) by reaction with simple alcohols on microwave irradiation. Under traditional heating conditions, the esterification does not take place, as in the cases of 1 and 3, or is highly incomplete, as in the case of 6. Steric hindrance in diphenylphosphinic acid prevents efficient microwave-assisted esterification. 相似文献
11.
Nikolaeva I. L. Burilov A. R. Pudovik M. A. Habicher W. D. Konovalov A. I. 《Russian Chemical Bulletin》2001,50(4):748-750
Calix[4]resorcinarene reacts with N,N,N",N"-tetraethyl-P-ethylphosphonous diamide to give dioxaphosphocines, whose hydrolysis with intracavity water yields phosphinoyl derivative of calix[4]resorcinarene. 相似文献
12.
Photolysis of aryl‐substituted 2,5‐dihydrophosphole oxides (5a–e and 8) in the presence of methanol afforded methyl aryl‐H‐phosphinates (2a–e) in good yields. In the case of 1‐ethyl‐, cyclohexyl‐, or ethoxy‐2,5‐dihydrophosphole oxides, the reaction was much slower (5f and 5h) or did not take place at all (5g). In such instances, the presence of an additional skeletal methyl group (7) or the use of the more strained 7‐phosphanorbornene derivatives (6) promoted the fragmentation‐related phosphorylations. Furthermore, the effect of the ring saturation in 8 and the possible extensions to 2‐phosphabicyclo[3.1.0]hexanes (10a and 10f), a 1,2‐dihydrophosphinine oxide (11), and a 1,2,3,4,5,6‐hexahydrophosphinine oxide (12) were also investigated. Model compounds with P‐phenyl substituent that are of sufficient ring strain (8, 10a, and 11) could be utilized well. 相似文献
13.
The reactions ofO-phenyl chloromethylphosphonochloridate and bis(chloromethyl)phosphinous chloride with sodium acetate afford the corresponding
acyloxyphosphonates and acyloxyphosphinates, which are readily transformed due to disproportionation into pyrophosphonates
and pyrophosphinates.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp 2383–2385, November, 1998. 相似文献
14.
Rhodium‐ and Iridium‐Catalyzed Asymmetric Addition of Optically Pure P‐Chiral H‐Phosphinates to Aldehydes Leading to Optically Active α‐Hydroxyphosphinates
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Qiang Li Dr. Tieqiao Chen Prof. Dr. Qing Xu Prof. Dr. Li‐Biao Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(18):6213-6217
Optically active α‐hydroxyphosphinates with both C‐ and P‐stereogenic centers are obtained by rhodium‐ or iridium‐catalyzed substrate‐directed stereoselective addition of the optically pure H‐phosphinates to aldehydes. The reaction most probably proceeds by a transition‐metal‐catalyzed mechanism with hydridometal complexes as key intermediates in the catalytic cycle. 相似文献
15.
Fire retarded poly(ethylene terephthalate) (PET) has been obtained by the incorporation of octamethyl polyhedral oligomeric silsesquioxane (OMPOSS) and Exolit OP950, a phosphinate-based compound, in recycled PET. The presence of Exolit OP950 only leads to intumescence explaining the improvement of the flame retardancy. The addition of OMPOSS leads to a synergistic effect considerably increasing the fire retarding performances of the polymer in terms of cone calorimetry and limiting oxygen index even if a small thermal stabilisation as well as a very poor dispersion of OMPOSS and OP950 into the matrix has been observed. 相似文献
16.
Zsuzsa M. Jászay Truong Son Pham Katalin Gönczi Imre Petneházy László Tőke 《合成通讯》2013,43(11):1574-1579
A simple and efficient solid/liquid phase-transfer catalytic diazo transfer reaction for the synthesis of diazocarbonyl, diazophosphonyl, and diazophosphinyl compounds is reported. 相似文献
17.
Qiuli Yao Prof. Dr. Chengye Yuan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(19):6080-6088
A highly enantioselective synthesis of α‐hydroxyphosphinates was achieved based on the L ‐proline‐catalyzed aldol reaction of α‐acylphosphinates and acetone. Due to the preexisting chirality at the phosphorus center, mixtures of two diastereomers of the α‐hydroxyphosphinates were obtained in moderate to good yields, with simultaneously high enantioselectivity for both diastereomers. The products could be converted into α‐hydroxy‐H‐phosphinates with satisfactory yields. Furthermore, an unprecedented oxidation–reduction reaction of the α‐hydroxyphosphinates or α‐hydroxy‐H‐phosphinates to form phosphonates was observed, and the mechanism involved in such a chemical transformation is discussed. 相似文献
18.
C. Dennis Hall Peter Speers Rosa Valero Francisco Perez Pla Donald B. Denney 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):143-146
Abstract The reaction of triphenylphosphonium cyclopentadienylide (1) with halogen-substituted p-benzoquinones (4) is shown to give a new class of dipolar (zwitterionic) dyes (5) containing phosphorus. The general structure of these molecules has been investigated by a combination of mass spectrometry and multinuclear (1H, l3C and 3lP) nmr using the specialist techniques of DEPT spectroscopy, homonuclear (COSY) and heteronuclear, 2-D nmr. In addition, stopped-flow (uv/vis) techniques have been used to study the kinetics of the reactions and hence demonsrate that the rate-limiting step is nucleophilic addition of the ylid to the quinone, followed by a rapid loss of halide ion. The mechanism follows the classical pattern associated with nucleophilic aromatic substitution in activated aryl halides. 相似文献
19.
H. Gonçalves J. P. Majoral 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):357-372
Abstract L'étude de l'hydrolyse de tetraoxaspirophosphoranes dérivés du pinacol et [sgrave] liaison P–C extracyclique a permis de mettre en évidence des équilibres esters cycliques–esters acycliques dépendant de différents facteurs (substituants, solvant, température, nature du milieu etc….). Les réactions d'hydrolyse peuvent ětre orientées sélectivement vers la formation soit de diesters soit de monoesters phosphoniques, cycliques ou acycliques. Cyclic-acyclic esters equilibria have been found in the study of pinacol derivated tetraoxaspirophosphorans hydrolysis. These equilibria depend on different factors (substituents, solvent, temperature, basicity etc….). Hydrolysis reactions can be directed towards the formation of either diesters or cyclic and acyclic phosphonic monoesters. 相似文献
20.
Mehrdad Pourayoubi Fatemeh Karimi Ahmadabad Hossein Eshtiagh‐Hosseini Monika Ku
erkov Vclav Eigner Michal Duek 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1181-1185
The mixed‐amide phosphinates, rac‐phenyl (N‐methylcyclohexylamido)(p‐tolylamido)phosphinate, C20H27N2O2P, (I), and rac‐phenyl (allylamido)(p‐tolylamido)phosphinate, C16H19N2O2P, (II), were synthesized from the racemic phosphorus–chlorine compound (R,S)‐(Cl)P(O)(OC6H5)(NHC6H4‐p‐CH3). Furthermore, the phosphorus–chlorine compound ClP(O)(OC6H5)(NH‐cyclo‐C6H11) was synthesized for the first time and used for the synthesis of rac‐phenyl (benzylamido)(cyclohexylamido)phosphinate, C19H25N2O2P, (III). The strategies for the synthesis of racemic mixed‐amide phosphinates are discussed. The P atom in each compound is in a distorted tetrahedral (N1)P(=O)(O)(N2) environment. In (I) and (II), the p‐tolylamido substituent makes a longer P—N bond than those involving the N‐methylcyclohexylamido and allylamido substituents. In (III), the differences between the P—N bond lengths involving the cyclohexylamido and benzylamido substituents are not significant. In all three structures, the phosphoryl O atom takes part with the N—H unit in hydrogen‐bonding interactions, viz. an N—H...O=P hydrogen bond for (I) and (N—H)(N—H)...O=P hydrogen bonds for (II) and (III), building linear arrangements along [001] for (I) and along [010] for (III), and a ladder arrangement along [100] for (II). 相似文献