First synthesis and electronic properties of cyano(oligo)phenothiazines

(Oligo)phenothiazinyl nitriles were synthesized in good to very good yields from bromo (oligo)phenothiazines via the Beller cyanation protocol either under conductive or under dielectric heating using NMP as a solvent. Their electronic properties were determined by absorption and emission spectroscopy and cyclic voltammetry. Cyano(oligo)phenothiazines display large Stokes-shifts (5800-8300 cm⁻¹) and substantial quantum yields (11-27%). Their reversible oxidation potentials are considerably shifted anodically due to the electron-withdrawing character of the cyano group.     

TEMPO-catalyzed oxidative dimerization and cyanation of indoles for the synthesis of 2-(1H-indol-3-yl)-3-oxoindoline-2-carbonitriles

A method for the combinative oxidative homo dimerization and cyanation of free indole derivatives catalysed by TEMPO along with silver carbonate was demonstrated for the first time This new methodology is both atom and step efficient and is applicable to a broad scope of substrates, allowing the synthesis of a range of synthetically valuable 2-(1H-indol-3-yl)-3-oxoindoline- 2-carbonitriles in moderate to excellent yields. Furthermore, selected compounds 6b and 6g exhibit moderate to good anti-schistosomicidal activities.     

Lewis base-catalyzed cyanation of Morita-Baylis-Hillman carbonates. Synthesis of allylamine derivatives

DABCO-catalyzed cyanation of MBH carbonates via 1,3-proton shift transfer is reported. The adducts of cyanation are converted in one step to allylic amines derivatives. The salient features of this reaction include readily available starting materials, mild conditions, broad substrate scope, high efficiency and valuable further applications. The process of the 1,3-proton shift transfer was conducted by a joint research of NMR and DFT calculation.     

Palladium-catalyzed domino Heck/cyanation: synthesis of 3-cyanomethyloxindoles and their conversion to spirooxoindoles

3′-Alkyl-3-cyanomethyloxindoles, prepared by a palladium-catalyzed domino Heck/cyanation, were efficiently converted to spiropyrrolidinyl-, spiropiperidinyl- and spirocyclopropyl-oxindoles. The so-obtained spirooxindoles bearing three diversity points were further functionalized via selective N-acylation, N-alkylation, N-sulfonylation, S_NAr reaction and Buchwald-Hartwig N-arylation reaction to reach diverse set of heterocycles.     

Zn(OTf)2—catalyzed direct cyanation of benzylic alcohols—a novel synthesis of α-aryl nitriles

This work demonstrates an efficient method to prepare α-aryl nitriles by direct cyanation of benzylic alcohol with TMSCN in the presence of a catalytic amount of Zn(OTf)₂ under heating condition. A variety of benzylic alcohols can be converted into the corresponding α-aryl nitriles in good to excellent yields.     

均相salen类配合物催化不对称氰化反应研究进展

手性α-氰醇类化合物在有机合成领域中的应用非常广泛,分子中α-碳原子上连接的羟基和氰基两个官能团很容易控制、转化为大量极其重要的合成中间体,包括：α-羟基酸、α-羟基酯,α-羟基醛、α-羟基酮、α-胺基酸和β-胺基醇等.这些化合物都是工业上合成医药、农化产品、     

Optimisation and scale-up of microwave assisted cyanation

A microwave enhanced palladium catalysed cyanation procedure was optimised for the final step of a production method for citalopram 2. The method was demonstrated on multigram batch scale for the synthesis of escitalopram (S)-2 and then in a stop-flow continuous process for citalopram.     

Highly efficient trialkylsilylcyanation of aldehydes, ketones and imines catalyzed by a nucleophilic N-heterocyclic carbene

The synthetic utility of N-heterocyclic carbenes was demonstrated by the trialkylsilylcyanation of aldehydes, ketones and imines. In the presence of a catalytic amount of 3a, the reactions with Me₃SiCN proceeded smoothly to give the corresponding cyanohydrin trimethylsilyl ethers or amino nitrile derivatives in good to excellent yields.     

A robust palladium-catalyzed cyanation procedure: beneficial effect of zinc acetate

Conditions that ensure a more reproducible Pd(0)-mediated procedure to convert aryl bromides to aryl cyanides have been developed that entail the use of zinc dust to keep the Pd in the zero oxidation state and zinc acetate to ensure high catalytic activity. This procedure is applicable to a wide range of substrates and obviates the need for stringent removal of oxygen from the reaction medium.     

Triphenylphosphine-Mediated Eco-Friendly Synthesis of (Z)-Diisopropyl-2-(Cyano(Aryl)Methylene)Hydrazine-1,1-Dicarboxylates Using Potassium Hexacyanoferrate(II) as a Cyanide Source

Abstract

A triphenylphosphine-mediated synthetic method for (Z)-diisopropyl-2-(cyano (aryl)methylene)hydrazine-1,1-dicarboxylates via one-pot three-component reactions using potassium hexacyanoferrate(II) as a cyanide source was described. This protocol has advantages of no use of strong toxic cyanating agents, high yield, and simple work-up procedure.