Synthesis of 2 H- indazolo[2,1- b ]phthalazine-1,6,11(13 H )-triones using 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium dihydrogen sulfate {DABCO(HSO 3 ) 2 (HSO 4 ) 2 } as a new ionic liquid catalyst

Introduction of Two New Brønsted Acidic Ionic Liquids for the Formamide and Formamidine Derivatization of Amines

“…In recent years, preparation and use of different types of catalysts in organic transformations became an important part of our ongoing research program . In continuation of these studies and in order to overcome the previously mentioned restrictions on the synthesis of formamides and N , N ′‐diaryl formamidines, we motivated to report new and straightforward one‐pot procedures to obtain these compounds using [DABCO](HSO 3 ) 2 (Cl) 2 and [DABCO](HSO 3 ) 2 (HSO 4 ) 2 as newly reported efficient ionic liquid catalysts …”

“…[30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] In continuation of these studies and in order to overcome the previously mentioned restrictions on the synthesis of formamides and N, N'-diaryl formamidines, we motivated to report new and straightforward one-pot procedures to obtain these compounds using [DABCO] (HSO 3 ) 2 (Cl) 2 and [DABCO](HSO 3 ) 2 (HSO 4 ) 2 as newly reported efficient ionic liquid catalysts. [31,32] First of all, to optimize the amounts of the catalysts, solvent and temperature, the reaction of 4-chloroaniline (1 mmol), and formic acid (1 mmol) was selected as the model for the preparation of formamides and studied in the presence of different amounts of [ formamidines from the condensation of amines and triethyl orthoformate. In order to optimize the reaction conditions, the condensation of 4-chloroaniline (2 mmol) with triethyl orthoformate (1 mmol) was studied in the presence of [DABCO] (HSO 3 ) 2 (Cl) 2 and [DABCO](HSO 3 ) 2 (HSO 4 ) 2 , and the results are tabulated in Table 1.…”

DABCO-based ionic liquids: green and recyclable catalysts for the synthesis of barbituric and thiobarbituric acid derivatives in aqueous media

“…58 At the second step and in a round-bottomed ask (100 mL) containing [DABCO](HSO 3 ) 2 (Cl) 2 (0.864 g, 2.5 mmol) equipped with a gas inlet tube for conducting HCl gas over an adsorbing solution (i.e., water), sulfuric acid (99.99%, 0.49 g, 5 mmol) was added drop-wise over a period of 5 min in an ice bath. Aer the addition was completed, the reaction mixture was le for 6 h to give [DABCO](SO 3 H) 2 (HSO 4 ) 2 as a white solid in 95% yield 12 (Scheme 1). The product was formed quantitatively and in high purity as assessed by melting point, Mass, Hammett acidity, FT-IR, 1 H NMR and 13…”

“…They cost less, they offered a vast range of new colors, and they imparted better properties to the dyed materials. 12 Many colors that can be seen everywhere are synthetic dyes. They are used in everything from clothes to paper, from food to wood and etc.…”

Deep eutectic solvent an efficient reaction medium for the synthesis of chromeno pyrazolo and indazolo phthalazine derivatives

“…Heterocyclic molecules containing nitrogen atom constitute the largest proportion of biologically active molecules . Chromeno pyrazolo and indazolo phthalazine derivatives constitute a bridgehead hydrazine as a group of nitrogen‐containing heterocyclic compounds, which possess a multiplicity of pharmacological properties including anti‐inflammatory, antimicrobial, antifungal, anticonvulsant, vasorelaxant, antitumor and cardiotonic activities . Due to the large biological activity of phthalazine compounds, number of methods have been reported such as ionic liquids, magnetic nanoparticles, solid supported catalysts, heteropolyacids, β‐cyclodextrin, microwave, sulfonic acid, alumina nanoparticles and p‐TSA …”