A new procedure for synthesis of $$\upalpha $$ α -aminophosphonates by aqueous formic acid as an effective and environment-friendly organocatalyst

Abstract

Aqueous formic acid (37%) as a green organocatalyst was used to synthesis of α-aminophosphonates in one-pot, three-component Kabachnik-Fields reaction. The structures of compounds were determined by FT-IR, 1 H-NMR and 13 C-NMR spectroscopy. After optimization of the experimental conditions, the reaction was carried out at 65 • C under solvent-free condition. Use of a nontoxic effective organocatalyst, easy work up process and low-cost cleaning procedure are from the main advantages of this research.

Humic Acid: A Green‐Catalyst‐Mediated Solvent‐Free Synthesis of Functionalized Diethyl(Phenyl(phenylamino)methyl)phosphonate

“…The phosphite nucleophile and imine electrophile in this reaction created an NÀ CÀ P bond. Previously reported methods of this recognized Kabachnik-Fields reaction involves a variety of catalysts such as HfCl 2 , [23] NbCl 5 , [24] TiO 2 , [25] ceric ammonium nitrate, [26] phosphomolybdic acid, [27] aqueous formic acid, [28] CeCl 3 • 7H 2 O, [29] zinc di(L-prolinate), [30] SbCl 3 /Al 2 O 3 , [31] BF 3 • OEt 2 , [32] gold complex, [33] nano-magnetic sulfated zirconia (Fe 3 O 4 @ZrO 2 /SO 4 2À ), [34] dodecatungstophosphoric acid (DTP/SiO 2 ), [35] dehydroascorbic acid capped magnetite (DHAA-Fe 3 O 4 ), [36] sulfated polyborate, [37] propylphos-phonic anhydride(T3P), [38] xan-than sulfuric acid, [39] oxalic acid, [40] Yttria-zirconia, [41] MgFe 2 O 4, [42] hydrophobic γ-Fe 2 O 3 -Cu-complex, [43] Fe 3 O 4 @SiO 2 -2mimSO 3 H. [44] In addition various solvents like, DMSO, DMF, THF, CH 3 CN, EtOH, CH 3 Cl, MeCN were also used in this type of protocol. The earlier approach for making α-amino phosphonates had a number of challenges such as low yields, hard reaction conditions, prolonged reaction periods, high reaction temperatures, use of toxic catalyst and hazardous solvent.…”

$${\hbox {SO}}_{3}\hbox {H}$$ SO 3 H -functionalized magnetic $${\hbox {Fe}}_{3} {\hbox {O}}_{4}$$ Fe 3 O 4 nanoparticles as an efficient and reusable catalyst for one-pot synthesis of $${\upalpha }$$ α -amino phosphonates

“…The basic method for the preparation of α-amino phosphonates, involves the condensation of a primary or secondary amine, a carbonyl compound (aldehyde or ketone) and dialkyl or trialkyl phosphite, [12][13][14][15][16][17] which have been promoted by Lewis or Brønsted acids such as Yb(OTf) 3 , 18 31 Scandium tris(dodecyl sulphate) Sc(DS) 3 , 32 BF 3 -Et 2 O, 33 aq. HCOOH, 34 (CO OH) 2 , 35 Cd(ClO 4 ) 2 •xH 2 O, 36 PEG-SO 3 H, 37 KH 2 PO 4 , 38 Magnetic nanoparticle, 39 Aluminium pillared interlayered clay (Al-PILC), 40 Pentafluorophenylammonium triflate (PFPAT), 41 and Cellulose-SO 3 H. 42 On the other hand, N-hydroxy-amino phosphonic acids which are fascinating biologically active compounds, are phosphorus analogue of N-hydroxy-αamino acid, which have an important role in many metabolic and biological processes. 43 N-hydroxy-αamino phosphonates were also announced as suitable synthons for pseudo peptides and illustrate herbicidal and growth-regulating activity.…”