Ultrasound assisted synthesis of 5–7 membered heterocyclic rings in organic molecules

Abstract

Ultrasound synthesis is a powerful technique that is being used increasingly to accelerate organic reactions as a green synthetic approach. Ultrasonication has offered advantages over conventional methods in terms of enhanced yields, shorter reaction time, high selectivity and minimal side reaction. The current investigation is the review of papers published from 2016 to 2022 for the synthesis of organic heterocycles under the effect of ultrasound irradiation. It is a comprehensive compilation of sonochemical processes as a versatile technique to achieve synthesis of numerous organic scaffolds from simple carbocyclic compounds to complex and biologically active heterocyclic structural molecules. This review encompasses the examples of ultrasound supported synthetic reactions of multicomponent one pot processes as well as different steps flow synthesis. Ultrasound assisted synthesis have been proved as an ecofriendly and benign approach for the synthesis of 5-7 membered heterocyclic rings, with one to three hetero atoms. Moreover Ultrasound synthesis has offered excellent yield in a vast majority of reactions under mild conditions without involving complicated purification procedures.

Sintesis dan Karakterisasi Surfaktan Lignosulfonat dari Lignin Alkali Standar dan Lignosulfonat Teraminasi dari Lignosulfonat Standar

“…Formaldehid yang digunakan tidak memiliki atom karbon alfa dan hanya memiliki dua atom hidrogen. Sifat tersebut menyebabkan formaldehid bersifat aldehida elektrofilik dibandingkan keton karena hidrogen dapat menggantikan salah satu gugus alkil yang ada [16]. Reaksi Mannich dapat dilakukan pada kondisi alkali, netral, atau asam.…”

“…Tahapan berikutnya adalah penstabilan kerangka aromatik serta gugus O-H pada kerangka fenol yang bermuatan positif melalui penambahan basa membentuk lignosulfonat teraminasi 9. Lignosulfonat teraminasi hasil sintesis kemudian dikarakterisasi menggunakan FTIR dan IFT [16]. Hasil spektrum FTIR tersebut dapat digunakan untuk mengetahui jenis gugus fungsi yang ada pada lignosulfonat teraminasi hasil sintesis.…”

Design, Synthesis, and Biological Evaluation of Novel Coumarin Analogs Targeted against SARS-CoV-2

“…One of the major reasons to design coumarin derivatives containing the 1,3-dicarbonyl moiety in this study was their varied pharmacological activities, such as antioxidant, antiviral, immunomodulatory, and anti-inflammatory properties, as described in Figure 1 [ 11 , 12 , 13 ]. β-diketones are common scaffolds that can be found in many natural products and have a variety of biological functions.…”

Recent developments using malononitrile in ultrasound-assisted multicomponent synthesis of heterocycles

“…By liaising with multiple electrophiles and nucleophiles, these varied reactivity paradigms facilitate the edification of heterocyclic scaffolds. These scaffolds comprise aldehydes, ketones, isocyanides, amines, and ylides, particularly within the ambit of ultrasound-assisted multicomponent reactions, thereby broadening the scope of chemical synthesis and diversification [24] , [25] . Harnessing this approach, researchers have adeptly accessed an expansive class of biologically active molecules, encompassing pharmaceuticals, agrochemicals, and materials.…”