A seven-step total synthesis of Hagen's gland lactones 1 and 2 starting from 1,2-O-isopropylidene-alpha-D-xylofuranose 3 is reported. The success of this short and practical synthesis depends on the use of two key reactions: a stereoselective nucleophilic substitution at the anomeric position of 5 and 6, which allowed the construction of the gamma-lactone ring, and an alkyl substitution reactio...

Solar photochemistry was proved to be efficient for the nucleophilic substitution of alkoxy groups by amines in alkoxynitrobenzenes. The results of the sun-induced photochemical substitution were comparable to the outcome of the same reaction under irradiation by a low-pressure mercury lamp. Using 4’-nitrobenzo-15-crown-5 as a starting material we obtained a polyether amino alcohol a precursor ...

An efficient synthesis of novel near-infrared electrochromic 6-substituted (NO2, Br) anthraquinone imides, i.e., 2a and 2b, was established. Bearing functional groups suitable for further structural modifications by nucleophilic substitution reaction and various metal-catalyzed coupling reactions (e.g., Suzuki coupling), 2a and 2b were easily transferred to 1a by reaction with 4-methoxyphenol a...

Application of a dynamic microwave power system in the chemical synthesis of some phenothiazine and quinoline derivatives is described. Heterocyclic ring formation, aromatic nucleophilic substitution and heterocyclic aldehydes/ketones condensation reactions were performed on solid support, or under solvent free reaction conditions. The microwave-assisted Duff formylation of phenothiazine was ac...

In the current study, amorphous silica nanoparticles were easily extracted from rice husk ash. The target composite was synthesized by the direct incorporation of chloropropyl groups through the condensation of nanosilica and 3-chloropropyl trimethoxysilane and then grafting of 1,3,5-triazine-2,4,6-triamine (Melamine) onto the propyl groups by the simple nucleophilic substitution reaction (RHA@...

A series of functionalized spiro[indoline-3,2'-oxiran]-2-ones was efficiently synthesized by Darzens reaction of phenacyl bromides with isatins both with N-alkyl groups and without N-substituent in the presence of potassium carbonate as a base catalyst. When two equivalents phenacyl bromides were used in the reaction, the N-substitution reaction of isatin also finished with the formation of spi...

The A+B-->0 reaction model with a surface reconstruction is analyzed. It is compared with another similar model for the A+1/2B2-->0 reaction [V. N. Kuzovkov et al., J. Chem. Phys. 108, 5571 (1998)], which mimics the CO oxidation reaction on the Pt surfaces. The effect of monomer B adsorption instead of dimer B2 is examined. It is shown that qualitative system features such as reactant concentra...

Kinetic isotope effects (KIEs) [9] are the effects on chemical reaction rates caused by isotopic substitution in the reacting system. KIEs report on bonding changes to the isotopic atom(s) when going from reactant state to transition state (TS). KIE studies are therefore of great use in solving mechanistic problems such as: (i) concerted or stepwise reaction? (ii) which is the rate limiting ste...

4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylat...

Direct catalytic decomposition of NO has the advantages being a simple process, producing no secondary pollution, and good for economy, which attracted extensive research in recent years. Perovskite-type mixed oxides, with an ABO3 or A2BO4 structure, are promising materials as catalysts due to their low cost, high thermal stability, and, course, performances. In this review, influence factors, ...