Letters in Organic Chemistry - Volume 12, Issue 5, 2015

An efficient and mild method for thioacetalization of 2-alkynylbenzaldehydes in the presence of a catalytic amount of silver triflate has been described. This reaction proceeded efficiently to generate 2-alkynylbenzaldehydes thioacetals in good to excellent yields at room temperature within short reaction time (no more than 30 min). This transformation was extremely easy to perform without the need of using anhydro Read More

During process development of Trifloxystrobin and Kresoxim-methyl fungicides, two impurities were identified. These impurities were isolated and characterized using LCMS, IR, 1H NMR, 13C NMR and elemental analysis. Structures of the impurities were further unambiguously confirmed by their independent synthesis. Structure of both impurities revealed that they possess methyl (E)-methoxyiminoacetate pharmacophore, r Read More

A novel one-pot and mild synthesis of benzoimidazole derivatives through the reaction of o-Phenylenediamine with aromatic aldehydes in the presence of MnO2 nanoparticles supported on silica as oxidizing agent under grinding conditions. The significant features of the present protocol are; simplicity of procedure, high products yields, purity of products, solvent-free condition, and easily work-up procedure.

The design and synthesis of 4-(2-adamantyl)phenylalkylamines 1-4 are described and their antiproliferative activity against four different tumor cell lines is reported.

The Friedel-Crafts acetylation of 2-acetylanthracene (2-AcAN) with AcCl and AlCl3 in 1,2-C2H4Cl2 gave a mixture of 1,6-diacetylanthracene (1,6-Ac2AN) and 1,7-diacetylanthracene (1,7-Ac2AN), while the Friedel-Crafts acetylation of 2-AcAN in nitrobenzene gave 2,7-diacetylanthracene (2,7-Ac2AN). Both reactions were highly regioselective. B3LYP/6-31G(d) calculations of diacetylanthracenes, their O-protonates and their σ-co Read More

Triethylborane (TEB) was found to be a mild, efficient, and acid catalyst in electrophilic substitution reaction of indoles with aldehydes compounds to afford the corresponding bis(indolyl)methanes. Vibrindole A (5) and bis(indolyl)methanes derivatives 16 and 18 were synthesized using this methodology. Compound 16 is an intermediary in the synthesis of the natural bisindoles arsindoline B (2) and streptindole (6). The struct Read More

A series of 2,6-bis(arylethynyl)anthraquinones was prepared via double Sonogashira coupling to 2,6-diiodoanthraquinone, and characterized with regard to their optical and electronic properties. Substitution with a derivatized phenylethynyl group produced a λonset of 366 nm (Eg = 3.4 eV), but the more highly conjugated 2,6-bis(9’-anthracylethynyl)anthraquinones exhibited a λonset of approximately 540 nm (Eg = 2.3 eV). P Read More

Density functional theory was used to study the tautomerization of 4-bromo substituted 1Hpyrazoles in different solvents. Mechanism and transition state structures of five tautomeric reactions were detected using quadratic synchronous transit with B3LYP method. The effect of solvent was considered with PCM method. We have found that the tautomerization is done through the transferring of hydrogen atoms between two Read More

2H-Chromene and its derivatives are an important class of organic compounds due to their wide range of biological activities such as antimicrobial, antiviral, antiimflamatory and antitubercular agents. In the present work we have synthesized ten new 2H-chromene derivatives [(E)-4-(2-phenyl- 2H-chromen-3-yl)but-3-en-2-one and its substituted analogues] following aldol condensation of 2Hchromene- 3-carbaldehydes with acet Read More

In the presence of KF as base and THF as solvent, the tandem Michael addition-elimination reaction of different 5-alkoxy-3,4-dihalo-2(5H)-furanones with aminomethyl benzimidazoles at room temperature gave 21 target compounds simultaneously containing both bioactive benzimidazole and 2(5H)-furanone moieties in yields of 62-88 % (mostly over 71 %). The structures of all the newly synthesized compounds were elucidate Read More