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1.
Solid-phase methodology has been rapidly and extensively applied to the preparation of small organic molecules recently1. Organic selenides are of considerable interest in academia because of their wide involvement as key intermediates in organic synthesis. However, organic selenides are highly malodorous and generally unpleasant and difficult to handle, especially because of their toxicity. Since the first organoselenium resin2 was reported in 1976, several groups have developed some organ…  相似文献   

2.
The solid-phase preparation of vinyl sulfones via a novel polystyrene-supported selenomethyl phenyl sulfone reagent has been reported.  相似文献   

3.
Summary. Aromatic aldehydes undergo condensation with quinaldines under microwave irradiation to afford structurally diverse styrylquinolines in high yields under solvent-free conditions. A comparison with the conventional method clearly indicates the advantages of the new protocol.  相似文献   

4.
A mild and efficient synthesis of highly substituted pyrroles using the reaction of triphenylphosphine, α-diketone, ammonium acetate, and dialkyl acetylenedicarboxylates is described.  相似文献   

5.
Polystyrene-supported vinyl sulfone reagent has been developed and used for solid-phase organic synthesis of 3-monosubstituted isoxazoles by 1,3-dipolar cycloaddition reaction with nitrile oxides and subsequent cleavage from the polymer support through an elimination reaction in the presence of potassium tert-butoxide. The advantages of this method include straightforward operation, good yield, and high purity of the crude products.  相似文献   

6.
Combinatorial chemistry and solid phase synthesis have recently emerged as powerful tools for the drug discovery process1. It might be argued that selenoxide syn- elimination provided the principal impetus for the development of organoselenium chemistry. [2, 3] Sigmatropic rearrangement2 of allylic selenium compounds is the most fundamental reaction in the field of synthetic organoselenium chemistry as well as selenoxide syn-elimination. However, organic selenides are highly malodorous and …  相似文献   

7.
8.
Poly[styrene(iodosodiacetate)]reacted with diaryl diselenides,followed by sodium azide,giving 1-azido-2-arylselenoalkanes regioselectively.The polymer reagent could be regenerated and reused.  相似文献   

9.
10.
The synthesis of alkyl selenides has attracted considerable attention1-3 during the last few years in view of their importance as reagents and intermediates in organic synthesis.4 Several methods have been described for the introduction of selenium into organic molecules starting from elemental selenium.1–3  相似文献   

11.
盛寿日  黄宪 《中国化学》2003,21(4):471-473
This letter describes a method for the stereoselective synthesis of polymer-supported vinylic selenides and their applications to synthesis of(E)-and(Z)-1,2-disubstituted ethenes on solid-phase by the couplig reaction with Grignard reagents under the catalysis of NiCL2(PPh3)2.  相似文献   

12.
13.
卟啉在结构上可视为是由4个吡咯类亚甲基的α-碳原子通过次甲基桥互联而形成的大分子杂环化合物,具有高度共轭结构。 随着卟啉与金属的配合物即金属卟啉的催化特性受到广泛关注,取代卟啉的高效合成日益显示出重要的学术和应用价值。 但是现有的丙酸法和乙酸/硝基苯法存在卟啉收率低、环境污染严重等问题,导致取代卟啉的成本居高不下,限制了其广泛应用。 本文利用乙酸/氧气法,在120 ℃下控制反应物浓度为0.24 mol/L,并在反应第一阶段(前30 min)通入氧气,得到四(4-溴苯基)卟啉(化合物d),产率高达53.8%。 该方法是高效合成取代卟啉的新方法,卟啉骨架形成和氧化两个反应同时进行,方法简单、绿色且收率高,有望大幅度降低取代卟啉的合成成本。  相似文献   

14.
An efficient one-pot synthetic strategy for 2-aminobenzoxazoles was developed from isothiocyanates and 2-aminophenol using triflic acid as a cyclodesulfurizing reagent.

Additional information

ACKNOWLEDGMENT

We are thankful to the Department of Science and Technology, government of India, for the research funding.  相似文献   

15.
A general and highly chemo‐ and regioselective synthesis of ketones from olefins by domino hydroformylation/aldol condensation/hydrogenation reaction has been developed. A variety of olefins are efficiently converted into various ketones in good to excellent yields and regioselectivities in the presence of a specific rhodium phosphine/base–acid catalyst system.  相似文献   

16.
Benzyl alcohol is a naturally occurring aromatic alcohol and has been widely used in the cosmetics and flavor/fragrance industries. The whole‐cell biotransformation for synthesis of benzyl alcohol directly from bio‐based L‐phenylalanine (L‐Phe) was herein explored using an artificial enzyme cascade in Escherichia coli. Benzaldehyde was first produced from L‐Phe via four heterologous enzymatic steps that comprises L‐amino acid deaminase (LAAD), hydroxymandelate synthase (HmaS), (S)‐mandelate dehydrogenase (SMDH) and benzoylformate decarboxylase (BFD). The subsequent reduction of benzaldehyde to benzyl alcohol was achieved by a broad substrate specificity phenylacetaldehyde reductase (PAR) from Solanum lycopersicum. We found the designed enzyme cascade could efficiently convert L‐Phe into benzyl alcohol with conversion above 99%. In addition, we also examined L‐tyrosine (L‐Tyr) and m‐fluoro‐phenylalanine (m‐f‐Phe) as substrates, the cascade biotransformation could also efficiently produce p‐hydroxybenzyl alcohol and m‐fluoro‐benzyl alcohol. In summary, the developed biocatalytic pathway has great potential to produce various high‐valued fine chemicals.  相似文献   

17.
Polyamines and polyamine toxins are biologically important molecules, having modulatory effects on nucleotides and proteins. Here we present an improved alkylation procedure, which allows sequential synthesis of polyamines and polyamine toxins on solid phase using N-protected aminoalkyl halides and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD) as base. The feasibility of the procedure is demonstrated with the synthesis of the native polyamine toxin, PhTX-433, as well as an analogue, PhTX-56, which is a very potent and subtype selective glutamate receptor antagonist.  相似文献   

18.
此文报道了一种室温下,水相中由丙二睛,二硫化碳,卤代烃和烷基异硫脲四组份、一锅煮反应合成多取代嘧啶类化合物的方法。该方法具有高效、反应条件温和、操作简单、适用范围广和环境友好等优点。  相似文献   

19.
Summary. 4-Phenylthiosemicarbazide reacts smoothly with dimethyl acetylenedicarboxylate in the presence of aldehydes or ketones under solvent free conditions to produce highly functionalized thiazolidine-4-ones.  相似文献   

20.
许家喜  杨俊海 《合成化学》1998,6(3):248-254
综述了固相法合成糖肽的最新进展,论述了合成策略和所用聚合物载体,这是一种很有前途的合成糖肽的方法,参考文献42篇。  相似文献   

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