An eco-friendly innovative halide and metal-free basic ionic liquid catalyzed synthesis of tetrahydrobenzo [b] pyran derivatives in aqueous media: A sustainable protocol

Exploring Untouched Variant of Bis(2‐methyl‐1H‐indol‐3‐yl)methane: Enhances Chemo and Mono‐Selectivity

“…[3] You can directly obtain indoles with various carbonyl functional groups by using both homo-and heterogeneous catalysts. These catalysts cover a broad spectrum, encompassing acid catalysts, [4][5][6][7][8][9][10][11][12][13][14] Nano catalysts, [15][16][17][18][19][20][21] supported catalysts, [22][23][24][25][26][27][28][29][30][31][32][33][34][35] metal catalysts, [36][37][38][39][40][41][42][43] ion exchange resin, [44] and enzymes. [45] Reactions catalyzed by acids in this context involve substances such as HCl, [46] P 2 O 5 , [47] Amberlyst-15, [48] and solidified acids.…”

A facile one-pot synthesis of tetrahydrobenzo[b]pyrans and 2-amino-4H-chromenes under green conditions

“… 14 Notably, several of these heterocycles hold promise in the treatment of conditions such as Schizophrenia, Alzheimer's, amyotrophic lateral sclerosis, Huntington's, Parkinson's, and Down's syndrome. These reactions employ a variety of catalytic systems, such as CeCl 3 ·7H 2 O, 26 Fe 3 O 4 @SiO 2 @NiSB, 27 , [DABCO-PDO][CH 3 COO], 28 Co 3 (PO 4 ) 2 , 29 NH 2 @SiO 2 @Fe 3 O 4 MNPs, 30 f rGO@Fe 3 O 4 @ZrCp 2 Cl 2 ionic liquid [PEMIM][OH], 31 and Nano-SiO 2 /DBN. 32 Moreover, alternative synthesis conditions like electrochemical conditions and microwave radiation have also been documented.…”

Fe3O4@nano-almondshell/Si(CH2)3/2-(1-piperazinyl)ethylamine as an effective magnetite almond shell-based nanocatalyst for the synthesis of dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyran derivatives

“…Dihydropyrano[3,2- c ]chromene and tetrahydrobenzo[ b ]pyran are heterocyclic organic compounds containing oxygen and are very attractive. For this reason, so far, many catalysts including ZnO NPs 30 , t-ZrO 2 NPs 31 , SB-DABCO@eosin 32 , Fe 3 O 4 @GO-NH 2 33 , [PEMIM][OH] 34 , [(EMIM)Ac] 35 , L-Proline 36 , Chitosan-ZnO 37 , CESA 38 , Glycine 39 , rGO@Fe 3 O 4 @ZrCp 2 Cl 2 40 , Fe 3 O 4 @ G.tea /Cu 41 , etc. have been used for the synthesis of this class of compounds.…”