Easy Access to α-Bromoketones and Epoxides from vic-Dibromides Under Aqueous Conditions

The conversion of vic-1,2 dibromides to α-bromoketones and epoxides using H₂O₂/dioxane and NaOH/water respectively under mild conditions has been described.     

Synthesis of 2,2′‐Bi‐2H‐3,3′‐diaryl‐1,4‐benzothiazines from α,α‐Dibromoacetophenones and o‐Aminothiophenol

Some 2,2′‐bi‐2H‐3,3′‐diaryl‐1,4‐benzothiazines (5a–f) were synthesized from α,α‐dibromoacetophenones and o‐aminothiophenol.     

Heteropoly Acids as Heterogeneous and Reusable Catalyst for α-Thiocyanation of Ketones

Simple, efficient, and mild method for α-thiocyanation of ketones in presence of heteropolyacid has been developed. This methodology offered α-oxothiocyanates in good to excellent yields at room temperature in a highly selective manner. The catalyst could be efficiently recovered from the reaction and reused.     

Stereocontrolled Transformations of trans α,β‐Aziridine Aldehydes toward Different Amino Hydroxylated Structures

The stereocontrolled condensation of methyl ketones to trans α,β‐aziridine aldehydes creates functionalized aldols, valuable precursors for different amino hydroxylated structures, such as amino alcohols, amino diols, α‐tetrahydrofuryl amides, and α‐furyl amides.     

A Versatile Method for the Preparation of Enantiomeric Benzene-1,2-bis(alanine) Derivatives

Abstract

A versatile method for the preparation of dicarba analogues of cystine as substituted benzene-, dihydrobenzene-, and tetrahydrobenzene-1,2-bis(alanine) derivatives is described. The partially saturated products resulted from Diels-Alder adduct formation with stereoselectively prepared (2R,7R)-2,7-diacetamido-4,5-bis (methylene)octane-1,8-dioic acid dimethyl ester. Aromatization of the dihydro adducts by manganese dioxide provided the parent benzene-1,2-bis(alanine) derivatives.     

One-Pot,Three-Component Coupling Reaction: Catalyst-Free Green Synthesis of Novel N-Heteroaryl α-Naphthylglycines

A series of novel N-heteroaryl α-arylglycines containing naphthol rings has been prepared by one-pot, three-component condensation reaction of glyoxalic acid, heteroaryl amines and naphthols in water at ambient temperature and under reflux conditions in moderate to high yields. The promising advantages such as removal of organic solvent, no need to catalyst, simplicity of the reaction procedure and easy product separation will be discussed in this article.     

Efficient Synthesis of the Cyanofluoromethylated Ketones: Michael Reaction of the Cyanofluoromethyl Anion Species to Unsaturated Ketones

Abstract

Synthesis of cyanofluoromethylated ketones is discussed. The Michael addition of α‐cyano‐α‐fluoromethyl anion species to α,β‐unsaturated ketones is investigated.     

Synthesis of 3-Trifluoromethyl-Substituted Benzo[f]chromene Derivatives in a One-Pot Reaction

In the presence of 1,8-diazabicycolo[5.4.0]undec-7-ene (DBU) and concentrated H₂SO₄, 2-naphthol reacted smoothly with α,β-unsaturated trifluoromethyl ketones in CH₂Cl₂ at room temperature, affording the 3-trifluoromethyl-substituted benzo[f]chromene derivatives in good to excellent yields in a one-pot reaction.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details].     

ZrOCl2·8H2O: An Efficient Catalyst for One-Pot Synthesis of α-Amino Phosphonates Under Solvent-Free Conditions

A highly efficient protocol has been developed for the three-component reaction of an amine, an aldehyde, and diethyl phopshite catalyzed by ZrOCl₂·8H₂O, an environmentally friendly catalyst, at ambient temperature. The catalyst exhibited remarkable activity and tolerated a wide variety of functional groups, providing the desired amino phosphonates in excellent yields under solvent-free conditions. Alternatively, the reaction rate can be significantly enhanced by carrying out the reaction in a monomode microwave reactor as a promoter.     

NaOH/Et3N-Promoted Stereoselective One-Pot Synthesis of α-Diazo Oxime Ethers via Diazo Transfer Reaction

For the first time, we have observed a combined effect of two bases NaOH/Et₃N to promote the diazo transfer reaction of β-oximino esters. This unusual synergistic effect has been employed to obtain α-diazo oxime ethers directly from β-keto esters by one-pot process. This method is simple and cost-effective and the reagents are readily available.