- Lewis Acid Promoted Aerobic Oxidative Coupling of Thiols with Phosphonates by Simple Nickel(II) Catalyst: Substrate Scope and Mechanistic Studies
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Exploring new catalysts for efficient organic synthesis is among the most attractive topics in chemistry. Here, using Ni(OAc)2/LA as catalyst (LA: Lewis acid), a novel catalyst strategy was developed for oxidative coupling of thiols and phosphonates to phosphorothioates with oxygen oxidant. The present study discloses that when Ni(OAc)2 alone was employed as the catalyst, the reaction proceeded very sluggishly with low yield, whereas adding non-redox-active metal ions such as Y3+ to Ni(OAc)2 dramatically promoted its catalytic efficiency. The promotional effect is highly Lewis acidity dependent on the added Lewis acid, and generally, a stronger Lewis acid provided a better promotional effect. The stopped-flow kinetics confirmed that adding Y(OTf)3 can obviously accelerate the activation of thiols by Ni(II) and next accelerate its reaction with phosphonate to generate the phosphorothioate product. ESI-MS characterizations of the catalyst disclosed the formation of the heterobimetallic Ni(II)/Y(III) species in the catalyst solution. Additionally, this Ni(II)/LA catalyst can be applied in the synthesis of a series of phosphorothioate compounds including several commercial bioactive compounds. This catalyst strategy has clearly supported that Lewis acid can significantly improve the catalytic efficiency of these traditional metal ions in organic synthesis, thus opening up new opportunities in their catalyst design.
- Xue, Jing-Wen,Zeng, Miao,Zhang, Sicheng,Chen, Zhuqi,Yin, Guochuan
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p. 4179 - 4190
(2019/04/30)
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- Echothiophate Iodide Process
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The present invention relates to a process for preparation of Echothiophate Iodide (I). Echothiophate Iodide (I) obtained by the process of the present invention is obtained as new crystalline form designated as Form-SET. The process for preparation of Echothiophate Iodide (I) according to present invention is an ecofriendly process that avoids the use of hazardous solvent systems and provides Echothiophate Iodide (I) of high purity. Pharmaceutical composition of the said crystalline Form-SET of Echothiophate Iodide (I) of high purity is useful in the treatment of ocular disorders like Glaucoma.
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Paragraph 0060; 0062-0063
(2017/01/23)
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- Cs2CO3-Catalyzed Aerobic Oxidative Cross-Dehydrogenative Coupling of Thiols with Phosphonates and Arenes
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An efficient Cs2CO3-catalyzed oxidative coupling of thiols with phosphonates and arenes that uses molecular oxygen as the oxidant is described. These reactions provide not only a novel alkali metal salt catalyzed aerobic oxidation, but also an efficient approach to thiophosphates and sulfenylarenes, which are ubiquitously found in pharmaceuticals and pesticides. The reaction proceeds under simple and mild reaction conditions, tolerates a wide range of functional groups, and is applicable to the late-stage synthesis and modification of bioactive molecules.
- Song, Song,Zhang, Yiqun,Yeerlan, Adeli,Zhu, Bencong,Liu, Jianzhong,Jiao, Ning
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supporting information
p. 2487 - 2491
(2017/02/23)
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- A thiophosphate synthetic method of compound and the method in a plurality of pharmaceutical application in the synthesis of (by machine translation)
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The invention discloses a having the general formula (III) of the thiophosphate synthetic method of compound, the purpose is to provide a novel, condition is simple, easy to industrial production of the thiophosphate synthetic method of compound. The method is to have the general formula (I) of the organophosphorus oxygen apperception compound having the general formula (II) with a mercaptan or phenyl-sulfhydryl apperception compound mixed, under the effects of catalyst, obtained by the reaction of the formula (III) of the thiophosphate compound. The method of the invention, can be cheap efficient synthesis of thiophosphate compounds, in actual production will have extensive application prospect. (by machine translation)
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Paragraph 0159; 0160; 0161; 0162
(2017/07/20)
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- SYNTHESIS OF S-DIALKYLAMINO THIOPHOSPHATES
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O,O-Dialkyl S-(2-dialkylaminoethyl) thiophosphates are obtained by the reaction of dialkylamino sulfenyl chlorides, sulfenamides, thiobisamines, and amino disulfides with neutral and acidic alkyl phosphites; in the case of sulfenamides the synthesis is carried out under acid-catalysis conditions using zinc chloride.N,N-Dimethylthiobisamine reacts with the neutral phosphite to give O,O-diethyl S-dimethylamino thiophosphate, while the reaction of the amino disulfide with sodium diethyl phosphite leads to 2-diethylaminoethyl ethyl sulfide.
- Petrov, K. A.,Rudnev, G. V.,Sorokin, V. D.
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p. 1012 - 1014
(2007/10/02)
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- Synthesis and properties of 2 S [2' (N,N dialkylamino)ethyl]thio 1,3,2 dioxaphosphorinone 2 oxide and of the corresponding quaternary derivatives as potential nontoxic antiglaucoma agents
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A new series of cyclic organophosphorus esters, 2 S [2' (N,N dialkylamino)ethyl]thio 1,3,2 dioxaphosphorinane 2 oxide and their quaternary derivatives, was synthesized and studied as potential antiglaucoma agents These compounds inhibit acetylcholinesterase (E.C. 3.1.1.7) at a bimolecular rate constant (k(i)) in the range of 103-104 M-1 min-1. Values of the affinity (K) and phosphorylation (k') rate constants for this enzyme indicate that k' is responsible for the relatively low values of k(i) as compared with similar data for the open chain analogues, O,O diethyl phosphorothiolates (106 M-1 min-1). The mammalian toxicity of the new compounds in terms of acute LD50 values in mice is 1-3 x 103 less than that of phospholine, an open chain analogue. In an initial clinical trial, one member of the new series (alkyl= C2H5) caused a significant decrease of intraocular pressure in aphakic glaucoma, while phospholine proved to be ineffective.
- Amitai,Ashani,Grunfeld,Kalir,Cohen
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p. 810 - 813
(2007/10/05)
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