Iridium Supported on Phosphorus‐Doped Porous Organic Polymers: Active and Recyclable Catalyst for Acceptorless Dehydrogenation and Borrowing Hydrogen Reaction

Abstract

Iridium-on-phosphorus-doped porous organic polymers (POPÀ Ir) were developed by anchoring simple iridium onto the skeleton of porous organic polymers through coordination bonds. This POPÀ Ir catalyst, which was thoroughly characterized by means of EDS, SEM, TEM, XRD, XPS, and FT-IR, revealed excellent catalytic activity for the reaction of diphenyl phosphinamide with benzyl alcohols through borrowing hydrogen strategy and acceptorless dehydrogenation with wide functional group tolerance. Moreover, this POPÀ Ir catalyst could be simply recovered and reused for at least five times without a significant loss of activity, and revealed considerable application prospects. The mechanism was investigated to further understand this POPÀ Ir catalytic system and transformations. Overall, the POPÀ Ir catalytic system has shown high activity and reusability in the borrowing hydrogen reaction between diphenyl phosphinamides and benzyl alcohols. Scheme 7. Recycling experiments. Scheme 8. The synthesis of 1,3,5-triazine derivative in a large scale.

Biguanide-Based Synthesis of 1,3,5-Triazine Derivatives with Anticancer Activity and 1,3,5-Triazine Incorporated Calcium Citrate Nanoparticles

“…Subsequently, the mixture was stirred under reflux for 14 h. Purification by silica gel column chromatography (eluent: 1:1 EtOAc/hexane to 5% EtOAc/MeOH) yielded 3e as a yellow solid (2.428 g, 40% yield). 1 H-NMR (400 MHz, DMSO) δ 9.93 (brs, 1H), 7.78 (d, J = 7.9 Hz, 2H), 7.56 (brs, 1H), 7.43 (brs, 1H), 7.28 (t, J = 6.8 Hz, 2H), 7.01 (t, J = 7.9 Hz, 1H), 3.83 (s, 3H); 13 4-amino-6-(phenylamino)-1,3,5-triazine-2-carboxylic acid (3f) was synthesised using a modified protocol from the literature [45]: NaOH (aq.) (50 mL, 1 M) was added to a solution of 3e (2.023 g, 8.25 mmol) dissolved in EtOH (100 mL).…”

“…A variety of synthetic routes exists for the 1,3,5-triazine derivatives, for example, three-component methods [ 5 , 6 ] or reactions between biguanides with alcohol [ 7 , 8 ], amide [ 9 ] or carboxylic acid derivatives [ 10 , 11 ]. As seen in many literatures, a biguanide like metformin has been frequently employed as the starting material [ 8 , 10 , 12 , 13 ]. Metformin-derived 1,3,5-triazine derivative HL010183 was shown to be 100 times more cytotoxic than metformin with IC 50 of 0.28 mM for both MDA-MB-231 and Hs578T cell lines [ 14 ].…”

“…1 H-NMR (400 MHz, DMSO) δ 13.49 (s, 1H), 9.77 (brs, 1H), 8.26 (d, J = 7.3 Hz, 1H), 7.76 (brs, 2H), 7.55 (brs, 1H), 7.44-7.35 (m, 2H), 7.33 (t, J = 7.2 Hz, 2H), 7.04 (t, J = 7.5 Hz, 1H), 6.90 (t, J = 8.0 Hz, 2H);13 C-NMR (101 MHz, DMSO) δ 169.9, 164.7, 160.8, 138.8, 133.2, 128.3, 128.1, 122.3, 120.2, 117.9, 117.2, 117.1; IR (neat): 3475, 3302, 3181, 1667, 1595, 1533, 1443 1429, 1031, 811, 752, 691; HRMS (ESI+): m/z calcd for C15H13N5O [M+H] + 280.1198, found 280.1205; Mp: 222-224 °C. (E)-N 2 -phenyl-6-styryl-1,3,5-triazine-2,4-diamine (3d): 1b was used without further purification.…”

“…Hz, 3H). ;13 C-NMR (101 MHz, CDCl3) δ 178.1, 166.3, 165.6, 38.8, 36.3, 32.1, 29.8, 27.7 22.8, 14.2. Data are consistent with literature values[43].…”

Silver/manganese dioxide nanorod catalyzed hydrogen-borrowing reactions and tert-butyl ester synthesis

“…In addition, Ag nano particles have been shown to have outstanding ability as catalyst in many organic reactions. [30][31][32][33] Based on our recent discoveries on hydrogen-borrowing reactions [34][35][36][37][38] and the properties of manganese oxides (MnO 2 ) nanorods and Ag nanoparticles, we herein report the synthesis and application of Silver/manganese dioxide (Ag@MnO 2 ) nanorods as a catalyst, which has higher catalytic activity after several cycles and which is much cheaper than other catalysts. The Ag@MnO 2 nanorods are characterized by several physical techniques.…”