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1.
Vijaya Kabra Suneeta Ojha Priti Kaushik Arpana Meel 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2337-2344
Eight novel amidothiophosphates have been successfully achieved using cycloiminium salts of pyridine as the starting material. Phosphorylation was done using phosphorus trichloride, and the resulting functionalized iminohalophosphines in situ were further oxidized and substituted through sulfur and a suitable secondary amine (alkyl, alicyclic, and aryl). The reactions were carried out in a dry nitrogen atmosphere. The synthesized products were characterized using different spectroscopic techniques (1H and 31P NMR). The pyridine nucleus incorporating a phosphoryl group is highly bioactive. Hence, the synthesized organothiophosphates should be potential pesticidal molecules. 相似文献
2.
Dr. Huijie Qiao Dr. Liting Yang Xiubei Yang Jialin Wang Ya Chen Dr. Lin Zhang Wuxuan Sun Dr. Lipeng Zhai Prof. Liwei Mi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202200600
Two new covalent organic frameworks (COFs) were synthesized from 4,4′,4′′,4′′′-(pyrene-1,3,6,8-tetrayl)tetraaniline and 2,5-dimethoxyterephthalaldehyde (Py-DMTA-COF) or 2′,5′-dimethoxy-[1,1′:4′,1′′-terphenyl]-4,4′′-dicarbaldehyde (Py-DMTPDA-COF) under solvothermal conditions. These two COFs were further facilely developed as efficient photocatalytic platforms for the synthesis of thiophosphinates. Py-DMTA-COF exhibited better photocatalytic activity, broad substrate applicability, and excellent recycling capacity for the preparation of thiophosphinates from P(O)H compounds and thiols compared to Py-DMTPDA-COF. This methodology was further extended to the seamless gram-scale production of target phosphorothioate derivatives. The results demonstrate that COFs can provide a robust platform for developing metal-free, base-free, highly efficient, and reusable heterogeneous photocatalysts for organic transformations. 相似文献
3.
Xue‐Feng Zhu 《合成通讯》2013,43(9):1346-1354
An improved and highly efficient synthetic approach to multibenzoylated nucleosides bearing free 5′‐hydroxyl groups is described here. By employing t-butyldimethylsilyl (TBDMS) rather than the more commonly used dimethoxytrityl (DMTr) as a temporary 5′‐OH protecting group of the starting nucleoside, this methodology provides the expected products in nearly quantitative yields, thereby substantially reducing the cost and effort of synthesis. 相似文献
4.
Olena I. Lukashuk Kostyantyn M. Kondratyuk Alexandr V. Golovchenko Vladimir S. Brovarets Valery P. Kukhar 《Heteroatom Chemistry》2013,24(4):289-297
It has been shown that the derivatives of diethyl 5‐amino‐2‐phthalimidoalkyl‐1,3‐oxazol‐4‐ylphosphonates can be employed in the synthesis of phosphorylated peptidomimetics containing the phosphonoglycine residue. The reaction of diethyl 5‐alkylamino‐2‐aminoalkyl‐1,3‐oxazol‐4‐ylphosphonates with unsaturated azlactones was utilized to obtain phosphorylated peptidomimetics with dehydroamino acid moieties. The double bond in the latter was reduced with zinc in acetic acid to provide the corresponding saturated peptidomimetics containing a diethoxyphosphoryl group in the side chain. 相似文献
5.
Stereoblock poly(lactic acid) (sb-PLA), consisting of poly(L-lactic acid) (PLLA) and poly(D-lactic acid) (PDLA) in a blocky sequence, can successfully be synthesized by solid-state polycondensation of a stereocomplexed mixture of PLLA and PDLA. First, the melt polyconden-sation of L- and D-lactic acids is conducted to obtain PLLA and PDLA with medium molecular weights. Then, both polymers are melt-blended to easily form the stereocomplex. The resulting stereocomplexed mixture (melt-blend) is subjected to solid-state polycondensation for chain extension. The molecular weight (Mw) of the resultant sb-PLA is strongly affected by the lactide/oligomer content in the melt-blend, which is determined by the melt-blending conditions, because it is directly correlated with the polymer crystallinity of the polycondensation products. 相似文献
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(±)‐Desoxynoreseroline ( 3 ), the basic ring structure of the pharmacologically active alkaloid physostigmine ( 1 ), was synthesized starting from 3‐allyl‐1,3‐dimethyloxindole ( 9 ). The latter was prepared from the corresponding 2H‐azirin‐3‐amine 6 by a BF3‐catalyzed ring enlargement via an amidinium intermediate 7 (Scheme 1). An alternative synthesis of 9 was also carried out by the reaction of N‐methylaniline with 2‐bromopropanoyl bromide ( 12 ), followed by intramolecular Friedel–Crafts alkylation of the formed anilide 13 to give Julian's oxindole 11 . Further alkylation of 11 with allyl bromide in the presence of LDA gave 9 in an excellent yield (Scheme 3). Ozonolysis of 9 , followed by mild reduction with (EtO)3P, gave the aldehyde 14 , whose structure was chemically established by the transformation to the corresponding acetal 15 (Scheme 4). Condensation of 14 with hydroxylamine and hydrazine derivatives, respectively, gave the corresponding imine derivatives 16a – 16d as a mixture of syn‐ and anti‐isomers. Reduction of this mixture with LiAlH4 proceeded by loss of ROH or RNH2 to give racemic 3 (Scheme 5). 相似文献
7.
Giacomo Biagiotti Ilaria Perini Barbara Richichi Stefano Cicchi 《Molecules (Basel, Switzerland)》2021,26(20)
The success of the rational bottom-up approach to nanostructured carbon materials and the discovery of the importance of their doping with heteroatoms puts under the spotlight all synthetic organic approaches to polycyclic aromatic hydrocarbons. The construction of atomically precise heteroatom doped nanographenes has evidenced the importance of controlling its geometry and the position of the doping heteroatoms, since these parameters influence their chemical–physical properties and their applications. The growing interest towards this research topic is testified by the large number of works published in this area, which have transformed a once “fundamental research” into applied research at the cutting edge of technology. This review analyzes the most recent synthetic approaches to this class of compounds. 相似文献
8.
An improved synthetic approach to tenatoprazole 1 is described. It started from 2,3,5‐trimethyl‐4‐nitropyridine‐N‐oxide 2 with acetic anhydride via rearrangement and hydrolysis to give 3, Chlorination with SOCl2 yielded 2‐chloromethyl‐3,5‐dimethyl‐4‐nitropyridine hydrochloride 4, then 4 condensed with 2‐mercapto‐5‐methoxy imidazole [4,5‐b]pyridine 5 to give 5‐methoxy‐2‐[(4‐nitro‐3,5‐dimethyl‐2‐pyridinyl)methylthio]imidazole[4,5‐b]pyridine 6. At last the title compound 1 was produced by two methods: 6 was oxidized with MCPBA and then methoxylated with CH3ONa to give 1 and 6 was first methoxylated with CH3ONa and then oxidized with MCPBA to give 1. The overall yield is around 26% for both five‐step syntheses. 相似文献
9.
It has long been known that homologous blood transfusion will result in a lot ofserious problems such as viral infections,for example AIDS,hepatitis,antigenicsensitization and GVHD;therefore aggressive testing of donor blood has beenadopted[1 ,2 ] .Even after this introduction,which is time-consuming and expensive,wecould not eliminate all the risks. In the wake of these kinds of pitfalls,production andclinical use of the blood substitutes have emerged.The essential aim of blood substitutei… 相似文献
10.
Matthias Schulze 《合成通讯》2013,43(22):3415-3422
Racemic fluoxetine was synthesized from 3-benzoylpropionic acid in five steps in 54% overall yield. 相似文献
11.
A series of caged 1,4-diols, 26, 29a/29b, 31 , were synthesized from the Diels-Alder cycloadduct 21 of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene and 1,4-benzoquinone. Reduction of enedione 21 with aqueous TiCl3, followed by base-catalyzed enolization in the presence of acetic anhydride, gave diene 23b , which reacted with maleic anhydride and 1,4-benzoquinone to produce the corresponding [4+2] cycloadducts 24b and 27 , respectively. The adduct 24b was converted to birdcaged 1,4-diol 26 by photocyclization followed by decarboxylative olefination of resulted caged anhydride 25b . The adduct 27 was photocyclized to cage compound 28 , which was aromatized to dihydroquinone 29a by acid-catalyzed enolization, or benzo-annulated compound 31 by reduction and dehydration. The birdcaged 1,4-diols 26 and 31 underwent fragmentation induced by (diacetoxyiodo)benzene to give enediones 38/39 and 41/42 , respectively. Photocyclization of 38 and 39 produced the corresponding caged compounds 43 and 44 , respectively, possessing homosecohexaprismane skeletons. The corresponding monohydrate 43a of 43 was structurally characterized by single-crystal X-ray diffraction. 相似文献
12.
Vinyl esters of carbonotrithioic acids have been stereoselectively prepared by the reaction of potassium carbonotrithioates with vinyl(phenyl)-iodonium tetrafluoroborates with retention or inversion of the configurations. 相似文献
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Summary: Blockcopolymers of 3-methyl-3-phenylcyclopropene and norbornene derivatives were synthesized via ROMP. The crossover reaction during ROMP blockcopolymerization was successfully monitored via MALDI-TOF MS in agreement with GPC and NMR-methods. 相似文献
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A new synthetic approach to elvucitabine started from L-xylose via the reactions of 10 steps in an overall yield of 20% was developed. The key steps included trimethylsilyl trifluoromethanesulfonate(TMSOTf)-mediated stereocontrolled β-glycosidation and exquisite choice of chloroacetyl group for the protection of hydroxyl groups as well as the corresponding deprotection under notably mild conditions. The structure of elvucitabine, in particular, the stereochemistry thereof, was unambiguously determined by comparison of the physical properties, such as 1H NMR data and the specific rotation, of the synthesized sample with those reported. 相似文献
18.
Pyrrole undergoes a regioselective zinc‐mediated acylation with 2‐bromobenzoyl chloride followed by a Cu‐catalyzed N‐arylation under microwave irradiation, delivering the important heteroaromatic of fluorazone. 相似文献
19.
Semenova A. M. Ezhikova M. A. Kodess M. I. Zapevalov A. Ya. Pestov A. V. 《Russian Journal of Organic Chemistry》2020,56(4):645-648
Russian Journal of Organic Chemistry - Transesterification of commercial titanium(IV) alkoxides with 2,2,3,3-tetrafluoropropan-1-ol, followed by in situ transesterification of mixed titanium(IV)... 相似文献
20.
A novel synthetic method for the preparation of aliphatic aldehydes from the corresponding carboxylic acids via 1,3‐dimethylbenzimidazolium salts is provided. 1,3‐Dimethylbenzimidazolium salts were rapidly reduced with sodium/ethanol and then hydrolyzed with hydrochloric acid to obtain aliphatic aldehydes, in which the 1,3‐dimethylbenzimidazolium salts can be readily achieved from the corresponding carboxylic acids. The mechanism for the reductive reaction of 1,3‐dimethylbenzimidazolium salts with sodium/ethanol was discussed. 相似文献