Recent advances in the green synthesis of Betti bases and their applications: a review

Amine-Functionalized Lignin as an Eco-Friendly Antioxidant for Rubber Compounds

“…35,36 Amination reactions can be considered as mixed aldol reactions, dehydration of alcohols, and addition of conjugates of amines all occurring in "one pot," and double amination reactions can also occur. 37,38 The presence of amine groups caused the dark brown KL powder to turn light brown following the reaction. FE-SEM images of the KL and AL particles are shown in Figure 1b,c, respectively, where the morphologies appear to be similar.…”

“…In the DETA/formaldehyde solution, formaldehyde reacted with the primary or secondary amine groups of DETA to form immonium ions, which were generated in the presence of a high electron density of carbon atoms. Subsequently, immonium ions reacted with the phenolic hydroxyl groups in lignin to introduce amine groups only at the ortho and/or para positions. , Thus, the H and/or G units with free phenolic hydroxyl groups were converted to C 5 amine-substituted units. , Amination reactions can be considered as mixed aldol reactions, dehydration of alcohols, and addition of conjugates of amines all occurring in “one pot,” and double amination reactions can also occur. , The presence of amine groups caused the dark brown KL powder to turn light brown following the reaction. FE-SEM images of the KL and AL particles are shown in Figure b,c, respectively, where the morphologies appear to be similar.…”

A Green Protocol for One‐Pot Pseudo Five‐Component Synthesis of a New Series of Bis‐Betti Bases Via Mannich‐Type Reaction

“…So far, various methods have been reported for the synthesis of aminonaphthols (Betti bases) using various types of naphthols, aromatic/heteroaromatic/aliphatic/cyclic amines instead of ammonia and aliphatic/aromatic aldehydes under various conditions in recent years. The synthetic routes for the synthesis of this scaffold have been reviewed [5–8] . Moreover, bis‐aminomethylnaphthols (bis‐Betti bases) have been synthesized using by the reaction of various types of dihydroxynaphthalens such as 2,6‐dihydroxynaphthalene and 2,3‐dihydroxynaphthalene with aldehydes and amines, [9–13] the reaction of diamines such as 2,6‐diaminopyridine, piperazine and p ‐phenylenediamine with naphthols and aldehydes, [14–15] and the reaction of dialdehydes such as terephthaldehyde and isophthalaldehyde with naphthols and amines [16–17] and reduction of bisdihydrooxazine structures [18] .…”

“…The synthetic routes for the synthesis of this scaffold have been reviewed. [5][6][7][8] Moreover, bis-aminomethylnaphthols (bis-Betti bases) have been synthesized using by the reaction of various types of dihydroxynaphthalens such as 2,6-dihydroxynaphthalene and 2,3-dihydroxynaphthalene with aldehydes and amines, [9][10][11][12][13] the reaction of diamines such as 2,6-diaminopyridine, piperazine and p-phenylenediamine with naphthols and aldehydes, [14][15] and the reaction of dialdehydes such as terephthaldehyde and isophthalaldehyde with naphthols and amines [16][17] and reduction of bisdihydrooxazine structures. [18] The Betti reaction produces racemic and nonracemic aminoalkylnaphthol ligands.…”

Three-Component Betti Condensation for Synthesis of Aminomethylnaphthols Incorporating Deoxy-isoequilenine Scaffold-Absolute Configuration and Application

“…11 The scope of the current knowledge on the synthesis and application of aminobenzylnaphthols has recently been demonstrated in review articles. [12][13][14][15][16][17] In most cases, various chiral amines are used in combination with different aldehydes to prepare chiral non-racemic aminobenzylnaphthols. [7][8][9]18,19 As a third component 2-naphthol is commonly used in the condensation reaction.…”