Current Organic Chemistry - Volume 19, Issue 21, 2015

The first part of the review brings forth the detailed synthesis of the known camphor-derived organocatalysts. Most synthetic steps are operationally simple, enabling the preparation of the corresponding catalysts on a larger scale. Frequently, the bicyclic framework of camphor is connected with a proline-derivative through a suitable spacer, which enables the preparation of a library of organocatalysts needed for the fine-tuning of a selected stereoselective transformation. The second part of the review focuses on the application of camphor-derived organocatalysts in various fields of asymmetric organocatalysis. Catalytic reactions are often conducted under mild reaction conditions giving the corresponding products in good to excellent stereoselectivities.

This review mainly discusses the various supporting tactics that have been used for the immobilization of Pd complexes, and Pd nanoparticles typically on biopolymers, and the different characterization techniques used for the resulting catalytic materials. The discussion also focuses on the detailed catalytic applications of these catalysts in various organic transformations such as oxidation, hydrogenation and C-C cross coupling reactions including Mizoroki-Heck, Suzuki-Miyaura, Sonogashira, Stille and Tsuji-Trost reactions.

This review is a compendium of major research in the area of photocatalytic deNOx technologies. Largely, the research can be divided into two major heads: photocatalytic oxidation (PCO) and photocatalytic reduction (PCR) though photocatalytic decomposition is also a viable technology. In this article, major emphasis has been given to the materials and mechanisms developed for the various reactions. Many further studies are needed on the technologies of photocatalytic NOx abatement in terms of research work followed by commercialization. After discussing many studies, an overall conclusion is drawn with the potential future research direction in photocatalytic de-NOx investigation.

We report on synthesis of 1,2-disubstituted benzimidazoles in pure water using nano-structured pyrophosphate Na2CaP2O7. Our findings showed that this heterogeneous catalyst exhibited high catalytic activity and high selectivity in the synthesis of 1,2- disubstituted benzimidazoles from direct cyclocondensation of aromatic aldehydes with substituted benzene-1,2-diamine in pure water. The salient benefits of this method rely on various factors namely: a simple procedure, mildness of the reaction conditions, short reaction times, operational simplicity, high chemoselectivity, low cost and recyclability of the catalyst.