Ethyl lactate: An Efficient Green Mediator for Transition Metal Free Synthesis of Symmetric and Unsymmetric Azobenzenes

Abstract

Ethyl lactate, a bio‐based completely degradable green solvent has been explored as an efficient reaction medium for the synthesis of symmetric as well as unsymmetric azobenzenes using various amines. As an environment friendly solvent, ethyl lactate has been found to have an interesting effect in this methodology for the formation of azobenzenes without the use of any transitional metal catalysts at room temperature.

Visible light-mediated synthesis of quinazolinones from benzyl bromides and 2-aminobenzamides without using any photocatalyst or additive

“…This result revealed that visible light was essential for product formation. The reaction time and molar ratio were other important factors affecting the reaction yield (Table 1, entries [11][12][13][14][15][16][17]. We attempted to improve the yield of the product by optimizing the 1a : 2a ratio.…”

“…In existing reports, the reaction of o-substituted anilines with aldehydes appears to be the most commonly used technique. Various compounds, such as acids, [12][13][14][15][16] ionic liquids, 17,18 enzymes, 19,20 nanomaterials, [21][22][23][24] and metals, [25][26][27][28][29][30] are commonly used to catalyze the synthesis of quinazoline compounds from 2-aminobenzamide and aromatic aldehydes (Scheme 2a). Benzyl bromide, a multifunctional C1 synthon, is a simple precursor that has been successfully used in various transformations.…”

4,4′-Dimethylazobenzene as a chemical actinometer

“…1) is commercially available. However, it can be synthesized in good yields, according to well-known procedures [45,46]. In the present study, we synthesized the compounds according to the procedure reported in the SI (Section 1).…”

β-Cyclodextrin: a supramolecular catalyst for metal-free approach towards the synthesis of 2-amino-4,6-diphenylnicotinonitriles and 2,3-dihydroquinazolin-4(1H)-one

“…We have developed a metal-free protocol using a supramolecular catalyst, β-cyclodextrin. 1 In terms of environmentally friendly and atom economy, water 2 as a reaction medium is highly advantageous.…”

“…Many strategies have been designed for synthesizing 2,3-dihydroquinazolin-4(1 H )-ones in the literature; however, the most widely used method is the straightforward condensation reaction between 2-aminobenzamide and aldehyde. Most of these methodologies use metal salts, 41 metal nano-particles 42 of Co, Fe, La, Ag, In, and Cu, p -TSA, 43 amberlyst-15, 44 acidic silica, 45 trifluoroethanol, 46 cyanuric chloride, 47 heteropoly acid, 48 organic acid, 49 I 2 , 50 NH 4 Cl, 51 and β-cyclodextrin. 52 Synthesis of this molecule via a one-pot three-component protocol in a greener pathway is very tricky.…”