Polystyrene-supported Benzyl Selenide: An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins

Solid-phase methodology has been rapidly and extensively applied to the preparation of small organic molecules recently1. It might be argued that selenoxide syn-elimination provided the principal impetus for the development of organoselenium chemistry. In addition, the required selenoxides are readily available from the oxidation of the corresponding selenides, which in turn can be prepared by the reaction of selenium-stabilized carbanions with various electrophilic substrates2. However, or…     

Solid-phase Synthesis of Vinyl Sulfones Using Polystyrene-supported Selenomethyl Phenyl Sulfone

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

Polymer-Supported Vinyl Sulfone as an Efficient Reagent for the Synthesis of 3-Monosubstituted Isoxazoles

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.     

Gold‐Catalyzed Intermolecular CS Bond Formation: Efficient Synthesis of α‐Substituted Vinyl Sulfones

A general method for the synthesis of α‐substituted vinyl sulfones makes use of a combination of a triazole gold complex and gallium triflate. This efficient C? S bond formation between simple terminal alkynes and sulfinic acids provides access to various α‐substituted vinyl sulfones.     

Asymmetric Decarboxylative 1,4‐Addition of Malonic Acid Half Thioesters to Vinyl Sulfones: Highly Enantioselective Synthesis of 3‐Monofluoromethyl‐3‐Arylpropanoic Esters

An asymmetric decarboxylative 1,4‐addition of malonic acid half thioesters (MAHTs) to 2‐aryl‐substituted vinyl sulfones has been developed, yielding adducts with excellent enantioselectivity (up to 97 % ee). In view of tuning pK_a values, a quinine‐based benzyl‐substituted thiourea was designed and demonstrated as the most efficient catalyst. The enantioselective synthesis of 3‐monofluorinated analogues of 3‐methyl indanone and (+)‐turmerone has been accomplished from decarboxylative 1,4‐addition adducts with satisfactory results.     

Polystyrene-supported Selenides and Selenoxide: Versatile Routes to Synthesize Allylic Alcohols

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 …     

An Efficient Microwave-Assisted Synthesis of Structurally Diverse Styrylquinolines

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.     

A Simple and Efficient Direct Method for the Synthesis of Symmetric Dibenzyl Sulfones from Sodium Dithionite and Benzyl Chlorides in Ionic Liquid

Summary. Symmetric dibenzyl sulfones were synthesized in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF₄) at 100°C from various benzyl chlorides and sodium dithionite in moderate yields.     

甲基乙烯基亚砜的合成

含亚砜基功能高分子可用作高分子药物载体,高分子螯合剂,高分子催化剂及气体分离膜材料等,近年来已引起各国学者的兴     

A Novel Synthesis of Fused Heterocyclic Sulfones

The applicability and synthetic potency of the novel reagent diethyl 2‐aryl‐3‐phenylsulfonylpropen‐1,1‐dicarboxylate 3 is reported. Compound 3 proved to be a key precursor in heterocyclic sulfones syntheses. Chemical and spectroscopic evidence for the structure of the newly synthesized compounds are described.     

Ti(Oi‐Pr)4 Mediated Olefination between Julia Reagent and Aldehydes under Mild Conditions: Facile Synthesis of Vinyl Sulfones

A novel Ti(Oi‐Pr)₄ mediated olifination between Julia reagent and aldehydes has been developed. By this method, a series of substituted vinyl sulfones are prepared under mild conditions, all products are exclusively E isomers. All the structures of these compounds were confirmed by ¹H NMR, ¹³C NMR HRMS and IR.     

由硫醚或亚砜氧化制砜的研究进展

对氧化硫醚或亚砜成为砜的方法作一评述,参考文献50篇.     

聚苯乙烯负载氯化铁催化一锅法合成β-氨基酮类衍生物

制备了聚苯乙烯负载型氯化铁催化剂(PS-FeCl3),并通过红外光谱、X射线衍射、扫描电子显微镜等技术手段进行了表征。 在PS-FeCl3催化下,以苯乙酮、芳醛和芳胺为原料,采用一锅法Mannich反应合成了一系列β-氨基酮衍生物。 制备的催化剂性能稳定,使用4次仍保持较高活性。     

Enantioselective Synthesis of Quaternary Carbon Stereocenters: Addition of 3‐Substituted Oxindoles to Vinyl Sulfone Catalyzed by Pentanidiums

A pentanidium‐catalyzed highly enantioselective conjugate addition of 3‐alkyloxindoles to phenyl vinyl sulfone has been demonstrated. This approach allows the construction of 3,3‐dialkyl‐substituted oxindole frameworks with high yield and excellent enantioselectivity (up to 99 %) under simple phase‐transfer conditions. A variety of oxindoles bearing all‐carbon quaternary stereogenic centers were obtained in the presence of 0.25 mol % pentanidium. Meanwhile, practicality was illustrated by a gram‐scale asymmetric synthesis of two 3,3‐dialkyl‐substituted oxindoles. The resulting adduct can be smoothly transformed to the natural product analogue in a short synthetic route.     

Efficient Route for the Synthesis of Highly Substituted Pyrroles

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

糖肽的固相合成

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。     

A Solid Phase Synthesis of Chalcones by Claisen-Schmidt Condensations

In previous papers1,2, we reported our recent findings that chalcone (l,3-dipheny1-2-propen-1-one) derivatives are novel potential antimalarials that are active against chloroquine-resistant strains of Plasmodium falciparum. According to our structure-activity relationships (SAR) and computer modeling data1,2, we expect the chalcone derivatives with hydroxyl functionality on one of the aromatic rings and with some other appropriate substitutions on the other ring will be even more potent as a…     

Enantioselective Solid‐Phase Peptide Synthesis Using Traceless Chiral Coupling Reagents and Racemic Amino Acids

The enantioselective condensing reagent 4,6‐dimethoxy‐1,3,5‐triazine (DMT)/strychnine/BF$\rm{{_{4}^{-}}}$ was obtained by treatment of 2‐chloro‐4,6‐dimethoxy‐1,3,5‐triazine (CDMT) with strychnine tetrafluoroborate. The reagent was useful under typical conditions of solid‐phase peptide synthesis (SPPS) with enantiomerically homogeneous substrates. By SPPS, desired dipeptides were obtained in 84–94% yield using 4 equiv. of racemic Fmoc‐Ala, Fmoc‐Phe, and/or Fmoc‐Tyr for 1 equiv. of Wang resin loaded with Gly, Ala, Leu, Phe, Glu(^tBu), and/or Pro, respectively. For all three Fmoc‐protected amino acids, the configuration of the enantiomer preferred under SPPS conditions was independent of the structure of the acylated component and identical to that established in condensations proceeding in solution. In all cases, the enantiomer ratios L /D (er) were in a similar range, and varied from 9 : 92 to 2 : 98 for alanine, and from 90 : 10 to 100 : 0 for aromatic amino acids. The synthesis of Ac‐L ‐Lys(Ac)‐D ‐Ala‐D ‐Ala‐OH from racemic Fmoc‐Ala gave an L /D ratio of 10 : 90 for the esterification of Wang resin, and 0 : 100 for the formation of peptide bonds.