Mesoporous aluminosilicate-catalyzed allylation of aldehydes with allylsilanes

Mesoporous aluminosilicate (Al-MCM-41) was found to catalyze the allylation of both aromatic and aliphatic aldehydes with allylsilanes although amorphous silica-alumina or mesoporous silicates (MCM-41, SBA-15) could not catalyze the reaction under the same reaction conditions. The solid acid catalyst Al-MCM-41 could be reused three times without significant loss of activity.     

Iron‐catalyzed efficient three‐component allylation of imine in aqueous media

Iron trichloride hexahydrate has proved to be a very effective catalyst for the three‐component condensation of aromatic aldehydes, amines and allyltributylstannane, which produces high yields of homoallylic amines in water in the presence of surfactant SDS. Copyright © 2009 John Wiley & Sons, Ltd.     

Sn‐mediated one‐pot four‐component allylation of aldimines

A convenient and facile method for the synthesis of homoallylic amines was disclosed. The one‐pot reaction of aldehydes, aromatic amines and allylic bromide with tin powder at room temperature could afford the homoallylic amines in good to excellent yield without any promoter or additive. The method is highly efficient and environmentally benign with low cost and concise manipulation. Copyright © 2014 John Wiley & Sons, Ltd.     

Synthesis of homoallylic amines and acylhydrazides by tin powder‐promoted multicomponent one‐pot allylation reactions

An efficient process for the synthesis of homoallylic amines and N′‐homoallylic hydrazides is developed from the one‐pot reaction of carbonyl compounds, amines or N‐acylhydrazines, allyllic bromide and tin powder using water as solvent. N‐Acylhydrazines are found to be more reactive than amines in these processes. They can react not only with aldehydes but also with ketones to give the corresponding N′‐homoallylic hydrazides. Copyright © 2016 John Wiley & Sons, Ltd.     

Phosphomolybdic acid catalyzed facile one‐pot synthesis of 2,4,5‐triaryl‐1H‐imidazoles from benzil and aromatic aldehydes

A facile one‐pot synthesis of 2,4,5‐triaryl‐1H‐imidazoles with better yields and shorter reaction time from the condensation of benzil, ammonium acetate and aromatic aldehydes using the catalyst phosphomolybdic acid is described     

Reaction of tertiary cyclopropyl silyl ethers with diethylaminosulfur trifluoride. Part 2: The Friedel-Crafts allylation and cyclopropylation of electron-rich aromatic compounds

The reaction of tertiary cyclopropyl silyl ethers with diethylaminosulfur trifluoride in electron-rich aromatic compounds causes the Friedel-Crafts alkylation to produce allylated or cyclopropylated aromatic compounds.     

Bismuth compounds in organic synthesis. A one-pot synthesis of homoallyl ethers and homoallyl acetates from aldehydes catalyzed by bismuth triflate

[reaction: see text] Three one-pot methods for the conversion of aldehydes to homoallyl ethers catalyzed by Bi(OTf)(3).xH(2)O (1 < x < 4) have been developed. The one-pot synthesis of homoallyl ethers can be achieved either by in situ generation of the acetal followed by its reaction with allyltrialkylsilane or by a three-component synthesis in which the aldehyde, trimethylorthoformate or an alkoxytrimethylsilane and allyltrimethylsilane are mixed together in the presence of bismuth triflate (0.1-1.0 mol %). In addition, a three-component synthesis of homoallyl acetates, which is achieved by reacting the aldehyde, acetic anhydride, and allyltrimethylsilane in the presence of bismuth triflate (3.0-5.0 mol %), has been developed. The use of a relatively nontoxic, easy to handle, and inexpensive catalyst adds to the versatility of these methods.     

An efficient BINAM-copper(II) catalyzed Ullmann-type synthesis of diaryl ethers

A wide range of diaryl ethers are synthesized from the corresponding aryl iodides and phenols through Ullmann type coupling reactions in the presence of a catalytic amount of easily available BINAM-Cu(OTf)₂ complex under mild reaction conditions. Less reactive aryl bromides have also been shown to react with phenols under identical reaction conditions to give good yields of the diaryl ethers without increasing the reaction temperature and time.     

Highly efficient three-component synthesis of protected homoallylic amines by bismuth triflate-catalyzed allylation of aldimines

Bismuth triflate catalyzes the allylation of a variety of in situ generated protected aldimines using aldehydes, primary carbamates, and allyltrimethylsilane in a three-component reaction. The reaction proceeds rapidly and affords the corresponding protected homoallylic amine in good yield (up to 86%). Scope and limitations of the aldehyde and carbamate components are reported.     

Iron(III) p-toluenesulfonate catalyzed synthesis of homoallyl ethers from acetals and aldehydes

Iron(III) p-toluenesulfonate, Fe(OTs)₃·6H₂O, is an inexpensive, versatile and commercially available catalyst for the allylation of acetals using allyltrimethylsilane to yield homoallyl ethers in moderate to good yields. The one-pot conversion of aldehydes to homoallyl ethers using alkoxysilanes has also been accomplished using Fe(OTs)₃·6H₂O as a catalyst. The use of mild reaction conditions and a relatively non-corrosive catalyst make this method an attractive option for the synthesis of a range of homoallyl ethers.     

Assembly of homoallylamine derivatives through iron‐catalyzed three‐component sulfonamidoallylation reaction

An efficient FeCl₃‐catalyzed three‐component reaction between aldehydes, sulfonamides and allylsilanes has been achieved, which provides a convenient, atom‐economic and green way to construct homoallylamine derivatives. In addition, this reaction exhibits excellent syn stereoselectivity with γ‐substituted allylsilanes.     

Highly efficient N‐Heterocyclic carbene–palladium complex‐catalyzed multicomponent carbonylative Suzuki reaction: novel practical synthesis of unsymmetric aryl ketones

Highly efficient and chemoselective N‐heterocyclic carbene palladium complexes‐catalyzed multicomponent carbonyltive Suzuki reaction with sodium tetraphenylborate used as phenylating reagent has been demonstrated in this article. Both electron‐rich and electron‐deficient aryl iodides gave unsymmetric aryl ketones in excellent yields. Copyright © 2007 John Wiley & Sons, Ltd.     

An efficient one‐pot synthesis of pyridazinones and phthalazinones using HY‐zeolite

The first one‐pot synthesis of pyridazinones and phthalazinones from arenes, cyclic anhydrides, and ArNHNH₂ in the presence of efficient recyclable heterogeneous catalyst, HY‐zeolite, in high yield and short reaction time is reported. J. Heterocyclic Chem., (2011).     

Iron‐catalyzed one‐pot oxidation/Knoevenagel condensation reaction using air as an oxidant

A green and highly efficient iron‐catalyzed one‐pot oxidation/Knoevenagel tandem reaction for the synthesis of α, β‐unsaturated nitriles from secondary alcohols and malononitrile has been achieved. The reaction performed under mild conditions with air as an oxidant, and provided the corresponding oxidation/Knoevenagel prudocts in good to excellent yields within short times avoiding the use of noble metal catalysts and bases. Remarkably, water is the only byproduct in this methodology. The reaction could be performed on a gram scale under the standard reaction conditions.     

An efficient one‐pot synthesis of pyrazolo[3,4‐b]pyridinone derivatives catalyzed by L‐proline

A series of 3‐methyl‐1,4‐disubstituted‐4,5‐dihydro‐1H‐pyrazolo[3,4‐b]pyridine‐6(7H)‐ones was synthesized via the three‐component reaction of aldehyde, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine, and Meldrum's acid catalyzed by L ‐proline. This protocol has the advantages of easier work‐up, milder reaction conditions, and high yields. J. Heterocyclic Chem., (2011).     

An efficient one‐pot synthesis of a new heterocyclic system with high‐fluorescent properties

Nucleophilic substitution of hydrogen in nitro derivative of imidazo[1,2‐a]pyridine has been used as a key step in the one‐pot synthesis of a new highly fluorescent heterocyclic system pyrido [1″,2″:1′,2′]imidazo[4′,5′:5,6]pyrido[2,3‐b]indole. J. Heterocyclic Chem., (2012).