Influence of phase transfer catalyst structure on selectivity

A concise review is given of systematic studies concerned with the tuning of regio-, frequentio-, chemo-, and diastereoselectivity by the structure or type of phase transfer catalyst.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2094–2101, November, 1995.     

Indole Derivatives. 142. Some Properties of [4-(2-Indolyl)phenyl]phenylmethane and 1-[4-(2-Indolyl)phenyl]-2-phenylethane

The reactions of 2-arylindoles with strong electrophiles take place with significant resin formation. It was shown that electrophilic substitution is directed into the indole ring and into the side chain. 1,7-Migration of the substituent is observed in the investigated systems.     

Alkylation of aniline withn-propyl alcohol over zeolites

The alkylation of aniline withn-propyl alcohol over ZSM-5 and Y zeolites has been studied. Ce-exchanged Y zeolites proved to be the most active for the alkylation of aniline byn-propyl alcohol. The reaction of N-propylaniline over zeolites has been investigated. N-alkylaniline decomposed over zeolites to aniline and alkene, which in turn rearrange to C-alkylanilines.n-Propyl derivatives were formed through an SN₂ type mechanism, while isopropyl derivatives were formed by an SN₁ type mechanism.     

可见光促进(氮杂)芳香胺与重氮乙酸乙酯的N-烷基化反应

本工作利用可见光催化剂和Lewis酸双催化体系,在可见光条件下实现了重氮乙酸乙酯与苯胺衍生物或氮杂芳烃的N-烷基化反应,合成了一系列α-氨基酸类化合物.该反应条件温和,有良好的官能团兼容性和底物普适性.机理验证实验证明该反应涉及了自由基机理,由重氮烷在光催化剂作用下通过proton-coupledelectrontransfer(PCET)过程形成了烷基自由基,并在Lewis酸催化作用下与胺发生自由基偶联反应形成N-烷基化产物.这种新的催化机制进一步丰富了重氮化合物在可见光化学反应中的应用类型与范围.     

A Precautionary Note Regarding Derivatization Of Secondary Amines With Dialkyeacetals Of Formamide Other Than The Diethyl Derivative A Correction

Abstract

In an earlier communication we reported GC-MS studios on the reaction products of secondary amino tricyclics and dimethylformamide. ¹ The diethyl acctal reaction products were identified as N-ethyl derivatives on the basis of mass spectroscopic analysis. In a follow-up study, we reported the same reaction products were formed from other DMF-dialkyl acetals, such as dimethyl and dipropyl acetals. ² In view of this unusual reaction we reinvestigated the structure of the reaction products utilizing alternative spectroscopic methods, viz. NMR and IR, and present a correction to our earlier work ()Desipramine (1 mg) was heated with DMF-diethyl acetal (100 μ 1) at 80°C. for 15 min. The product: was dissolved in ethyl acetate (5 ml), extracted into 1 ml of 0.5 N HCl and back extracted into ethyl acetate at pH 11.0. The organic extract was dried over anhydrous sodium sulfate and evaporated to dryness under nitrogen. The resulting residue was used directly in the NMR and IR studies.     

Preparation of 4-(azol-1-yl)butyric acids by the interaction of azoles with γ-butyrolactone

The interaction of salts of imidazole, 1,2,4-triazole, benzimidazole, and 2-benzylbenzimidazole with γ-butyrolactone has been studied. Ab initio quantum-chemical calculations showed a preference for N-alkylation on interaction of azolates with γ-butyrolactone. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6. pp. 910–916, June, 2007.     

An efficient homogeneous gold(I) catalyst for N-alkylation of amines with alcohols by hydrogen autotransfer

A new and highly efficient homogeneous [Ph₃PAuCl]/AgOTf catalytic system was developed in N-alkylation reaction of primary amines with alcohols through a hydrogen autotransfer process. This Au(I) catalytic system shows excellent selectivity for mono-alkylation of primary amines with benzyl alcohol under moderate temperature of 100 °C (only secondary amines as product). The possible mechanism of this hydrogen autotransfer reaction with the catalytic system was proposed.     

New Approach to Synthesize Symmetrical and Unsymmetrical 6-(N-Alkyl(Aryl)Amino)- and 6-(N,N-Dialkyl(Aryl)Amino)-2,4-Bis(Alkyl(Aryl)Thio)Pyrimidines as anti-Platelet Agents

Abstract

A new and straightforward procedure has been developed for the preparation of symmetrical and unsymmetrical 6-(N-alkyl(aryl)amino)- and 6-(N,N-bisalkyl(aryl)amino)-2,4-bis(alkyl(aryl)thio)pyrimidines. The two identical or different alkylthio groups were successfully introduced into the pyrimidine ring of 4-amino-6-hydroxy-2- mercaptopyrimidine via S-alkylation with alkyl halides, and via a nucleophilic displacement with sodium alkylmercaptides, affording the key intermediate symmetrical and unsymmetrical 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines. Subsequently, N-alkylation of the 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines with alkyl halides conveniently gave the desired products. The human anti-platelet activities of all the synthesized new compounds were also evaluated.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

A green synthesis of chemiluminescent N-sulfopropyl acridinium esters in ionic liquids without using the carcinogen 1,3-propane sultone

Chemiluminescent acridinium dimethylphenyl esters containing hydrophilic N-sulfopropyl groups in the acridinium ring are used as labels in automated immunoassays for clinical diagnostics. Introduction of the N-sulfopropyl group in these labels is normally accomplished by N-alkylation of the corresponding, nonchemiluminescent acridine ester precursors with the toxic carcinogen 1,3-propane sultone. In the current study, we report that sodium 3-bromopropane sulfonate in ionic liquids (ILs) is a benign alternative to 1,3-propane sultone for introducing the N-sulfopropyl group in chemiluminescent acridinium ester labels. The sultone reagent can be eliminated in the synthesis of N-sulfopropyl acridinium dimethylphenyl ester labels by taking advantage of the increased reactivity of acridan esters toward nontoxic sodium 3-bromopropane sulfonate in [BMIM][BF₄]. Sodium 3-bromopropane sulfonate in ILs is also potentially a nontoxic alternative to 1,3-propane sultone for introducing the water-soluble, three-carbon sulfobetaine moiety in other molecules as well.     

二(N-十二烷基-N,N-二羧甲基铵基)-联苯二苄的合成

在氯乙酸钠存在下,二(N-十二烷基)-联苄胺经N-烷基化反应合成了新型双子表面活性剂——二(N-十二烷基-N,N-二羧甲基铵基)-联苯二苄(1)。1的结构经IR确证。