Nano-sawdust-OSO3H as a new, cheap and effective nanocatalyst for one-pot synthesis of pyrano[2,3-d]pyrimidines

Synthesis of chloro, fluoro, and nitro derivatives of 7‐amino‐5‐aryl‐6‐cyano‐5H‐pyrano pyrimidin‐2,4‐diones using organic catalysts and their antimicrobial and anticancer activities

“…Pyrimidines are generally synthesized by a Biginelli multicomponent reaction (MCR), a method considered green since they are fast, solvent free, produces good yields, and avoids exposing the environment to environmentally harmful intermediates . Pyrano[2,3‐ d ]pyrimidines are commonly formed from barbituric acid, malonitrile, and aldehdyes with a catalyst such as 1,4‐diazabicyclo[2,2,2]octane (DABCO), an organic catalyst, a mesoporous solid acid catalyst (SBA‐15‐Pr‐SO 3 H), a ZnFe 2 O 4 nanocatalyst, a nano‐sawdust‐OSO 3 H catalyst, a Mn‐doped ZrO 2 catalyst, or triethylammonium acetate (a green catalyst) . The same compounds were made using arylidenemalonitrile with barbituric acid under microwave irradiation without a catalyst or using ionic liquid catalysts such as N ‐butyl‐ N ‐methyl imidazole tetrafluoroborate [BMIm]BF 4 , N ‐ethyl‐ N ‐methyl imidazole tetrafluoroborate [EMIm]BF 4 , or N ‐butyl pyridinium tetrafluoroborate [BPy]BF 4 .…”

Introduction of organic/inorganic Fe3O4@MCM‐41@Zr‐piperazine magnetite nanocatalyst for the promotion of the synthesis of tetrahydro‐4H‐chromene and pyrano[2,3‐d]pyrimidinone derivatives

“…Because of the aboved mentioned very important characteristics, various synthetic procedures have been reported for the synthesis of tetrahydro‐4 H ‐chromenes and pyrano[2,3‐ d ]pyrimidinones using acidic and basic catalysts such as metformin‐modified silica‐coated magnetic nanoparticles (MNPs) (Fe 3 O 4 /SiO 2 ‐Met), Fe 3 O 4 @SiO 2 /DABCO, γ‐Fe 2 O 3 @HAp Si(CH 2 ) 3 AMP, high surface area MgO, N‐ methylimidazole, tetrabutylammonium bromide, trisodium citrate, p ‐dodecylbenzenesulfonic acid, poly (4‐ vinylpyridine), potassium phthalimide‐ N ‐oxyl, [cmmim]Br and [cmmim][BF4], choline chloride (ChCl), starch solution, (diacetoxyiodo)benzene (DIB) (for the synthesis of tetrahydro‐4 H ‐chromenes), diammonium hydrogen phosphate (DAHP), L ‐proline, KAl(SO 4 ) 2 .12H 2 O (alum), tetrabutylammonium bromide (TBAB), DABCO, sulfonic acid nanoporous silica (SBA‐Pr‐SO 3 H), Al‐HMS‐20, Nano‐ sawdust‐ OSO 3 H, ZnO‐supported copper oxide, succinimidinium hydrogensulfate ([H‐Suc] HSO 4 ) and [H 2 ‐DABCO][H 2 PO 4 ] 2 (for the synthesis of pyrano[2,3‐ d ]pyrimidinones). However, aforementioned methods suffer from some drawbacks such as low yields, extended reaction times, harsh reaction conditions, tedious work‐up procedures, toxic solvents and application of the expensive or unavailable catalyst.…”

Preparation and characterization of BF3 supported on coconut shell as a novel and effective nano-catalyst for one-pot synthesis of pyrano[2,3-d]pyrimidines

“…Recently, nano-solid-supported reagents such as nanocrystalline TiO 2 -HClO 4 [17], nano-TiCl 4 •SiO 2 [18], nano-SnCl 4 •SiO 2 [19], nano-sawdust-BF 3 [20], nano-sawdust-OSO 3 H [21], BF 3 -SiO 2 nano-particles [22], HClO 4 -SiO 2 nano-particles [23], nano-cellulose-OSO 3 H [24], nano-silica sulfuric acid [25], SbCl 5 /SiO 2 nano-particles [26], Pt@GO-PVP nano-composite [27], RhPt/TC@GO NPs [28], graphene oxide [29], and monodisperse Pt NPs@AC [30] have developed due to the high activity and selectivity [31].…”

“…During the course of our studies and investigations on the synthesis of pyrano[2,3-d]pyrimidine compounds and our interest in MCRs [20][21][22][23][24][25], we intended to study the feasibility of synthesizing their derivatives by the one-pot threecomponent condensation reactions strategy of aromatic aldehydes (1a-j) with ethyl cyanoacetate or malononitrile 2 and barbituric acid 3 in the presence of boron trifluoride supported on coconut shell (nano-BF 2 O-coc) as a novel nanocatalyst at reflux ethanol (Scheme 1).…”