Boric acid: an efficient and environmentally benign catalyst for transesterification of ethyl acetoacetate

Boric acid-catalyzed multi-component reaction for efficient synthesis of 4H-isoxazol-5-ones in aqueous medium

“…Recently, the organic synthesis of boric acid has attracted great interest because it is commercially available, environmentally benign, inexpensive, and easy to handle. Recently, this reagent has been used in various reactions including aza-Michael reaction [20], transesterification of ethyl acetoacetate [21], oxidation of sulfides [22], Biginelli reaction [23], and Mannich reaction [24]. In addition, it has also been used for the preparation of compounds such as the synthesis of 1,5-benzodiazepine derivatives [25], 2-amino-3,5-dicarbonitrile-6-thio-pyridines [26], 1-amidoalkyl-2-naphthols [27], dibenzoxanthenes [28], a-aminophosphonates [29], b-acetamido ketones [30], and a-hydroxyamides [31].…”

Boric acid as cost-effective and recyclable catalyst for trimethylsilyl protection and deprotection of alcohols and phenols

“…On the basis of the previously reported mechanisms for the catalytic application of boric acid in organic synthesis, [21][22][23][24] one idea for trimethysilylation of hydroxyl compounds is that boric acid acts as a Lewis acid, which may polarize the Si-N bond in hmds by coordinating with the nitrogen (Scheme 3). However, at this time the precise role of boric acid is not clear and should be further studied in detail.…”

“…Boric acid was recently shown to have a good profile for substituting for conventional acidic catalytic materials. [21][22][23][24][25][26] These properties prompted us to select boric acid as the catalyst in the present work.…”

Boric acid catalyzed one-pot synthesis of [1,2,4] triazolo quinazolinone Derivatives

“…Hence the development of rapid, simple, efficient, clean, high yielding, environmentally benign protocol using new catalyst for the synthesis of this compound is desirable. Boric acid is a water soluble inexpensive, stable, readily available, easy to handle catalyst and has been found effective in various transformations such as synthesis of aza Michael 17 , thia Michael 18 , transesterification of ethylacetoacetate 19 ,synthesis of α-hydroxyamides 20 , bromination, oxidation of sulphides 21 , beginelli reaction 21 , 1,5-benzodiazepine derivatives 22 , 2-amino,3-5 dicarbonitrile-6-thio-pyridene 23 . It is therefore important to examine the behavior of boric acid as a catalyst in the synthesis of 1,2,4-triazolo quinolinone derivatives.…”