Current Green Chemistry

To protect our loving ‘Mother Nature’ from the ever increasing chemical pollution associated with the organic transformations, scientists are continuously trying to modify their chemical processes to make them environmentally benign and sustainable. As a result, the last decade has shown tremendous progress in green credentials in organic transformations. The special thematic issue ‘Organic transformations by following green credentials- Part 1 (A)’ intends to highlight the current progress on the development of various organic transformations with special emphasis on greener aspects. The present issue consists a total of five review articles contributed by the leading scientists working in this field. Nowadays, photo-irradiated technique is treated as the most sustainable strategy. Sometimes organic transformations are not possible to carry out at room temperature by using conventional strategies, but in many occasions, those reactions were accomplished easily under photochemical conditions. As a result, photo-induced strategy has become a valuable tool for the synthesis of diverse organic scaffolds. The first contribution of this thematic issue by Kaur et al. deals with an up-to-date literature on the photo-induced synthesis of various fused five-membered oxygen containing heterocycles. Recently, spirooxindoles, specially of 3,3'-spirooxindoles, have drawn considerable attention as many of these scaffolds possess significant biological activities. As a result, a large number of methods are being reported for the synthesis 3,3'- spirooxindoles under various reaction conditions. In the second contribution, Deepthi et al. summarizes the recent literature related to the synthesis of 3,3'-spirooxindoles by using green credentials that include aqueous mediated reactions, multicomponent strategies and photocatalysis. Aziridines are being used as versatile precursors of various naturally occurring bioactive compounds including amino sugars, β-lactams, alkaloids etc. They are also being used as a versatile intermediate in many organic syntheses due to their susceptibility to ring-opening by facile C-N bond cleavage. In the third contribution, Santra and his group summarized recent developments related to the synthesis of various aziridines scaffolds under different reaction conditions. During the last few years, constant efforts have been made to carry out C-H functionalization reaction under greener conditions. A number of modifications were reported for the C-H functionalization reactions to make them eco-friendly and sustainable. The fourth contribution by Sarkar and Mukhopadhyay describes the current development of C-H functionalization carried out in aqueous medium and its synthetic utilities according to carbon-carbon and carbon-heteroatom bond formations under green conditions. Pyrazole and its related derivatives are very common in naturally occurring bioactive molecules. Many drug molecules contain pyrazole as the core structural unit. As a result, a large number of methods were reported for the efficient synthesis of these significant scaffolds. The last contribution by Singh and Nath offers an up-to-date literature on the synthesis of various substituted and fused pyrazole scaffolds under greener conditions. Though today organic chemists are paying much attention to green chemistry practices, we need to adopt green credentials as much as possible in our protocols to fulfill the challenges of sustainability. I feel honored and really grateful to all the contributors for their efforts to design this special thematic issue for Current Green Chemistry (CGC). I am very much thankful to the senior journal manager and the entire editorial team of Current Green Chemistry specially Ms. Humaira Bilal madam for her continued support. No words are sufficient to express my gratitude to Prof. (Dr.) György Keglevich (Editor-in-Chief) Sir for his unconditional help and encouragement in each step. I am also thankful to the respective reviewers for their valuable comments and suggestions to improve the quality of this special issue.