Fabrication of Flexible Co‐salen Integrated Polymers for Hydration of Epoxides and Alkynes via Cooperative Activation

Abstract

Most cross-linked polymers with integrated active sites in the network have poor flexibility, which inhibits their applications in catalysis involving a cooperative activation pathway. Herein, a flexible organic polymer with high concentration of salen ligand in the network (SOP) was successfully synthesized by the reaction of meso-1,2-diphenylethylenediamine and 1,3,5-tris(3'-tert-butyl-4'-hydroxy-5'-formylphenyl)benzene. The post-synthesis coordination with Co II followed by further oxidation results in the formation of SOPÀ CoÀ OTs. The large amounts uptake of benzene of SOP and variation of the BET surface area after coordination with different metal cations confirmed the network flexibility. Consequently, SOPÀ CoÀ OTs could efficiently catalyze the epoxides hydration to afford turnover frequency up to 2400 h À 1 via cooperative activation. Furthermore, SOPÀ CoÀ OTs works cooperatively with Amberlyst-15 in the hydration of phenylacetylene to afford higher yield than homogeneous Co-salen. Our primary results suggest the potential applications of flexible polymer catalysts in reactions involving cooperative activation pathway.

Complex isomerism influencing the textural properties of organometallic [Cu(salen)] porous polymers: paramagnetic solid-state NMR characterization and heterogeneous catalysis

“…49,50 Another catalytic utilization of metallosalen-containing POPs was in halogenation, 51 the Henry reaction 52 or epoxide hydration. 53…”

“…49,50 Another catalytic utilization of metallosalen-containing POPs was in halogenation, 51 the Henry reaction 52 or epoxide hydration. 53 The characteristics and the catalytic activity of salen-type complexes can be influenced by the type of complexed metal ion, the substituents on the salicylidene segments of the ligand, and the character of the central diamine part of the ligand. The diamine part of the ligand can significantly affect the geometry of the complex.…”

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF3: the case of alkyne hydration. Chemistry vs electrochemistry

“…However, the toxicity and the environmental issues associated with the use of mercury-based compounds have stimulated the search for alternative catalysts and conditions for the hydration of alkynes, in order to identify safer and more sustainable methods [11][12][13]. In particular, transitionmetal catalysts containing Au(I) or (III) [14][15][16][17][18][19][20][21][22][23][24], Ru(II) [25][26][27][28][29][30], Pd(II) [31][32][33], Pt(II) [34,35], Fe(III) [36,37], Cu(I) [38][39][40][41], Co(III) [42][43][44], as well as other metals, have been widely studied. In addition, methods involving Brønsted acids, alone or in presence of Lewis acids as co-catalysts, have been developed [45][46][47][48][49][50][51][52][53][54].…”

Highly Efficient Hydration of Epoxides under Atmospheric Pressure and Low Water/Epoxide Ratios by a Tunable Azolate Ionic Liquid through Anion–Cation Synergetic Catalysis

“…However, the production process such as liquid-phase thermal hydration usually needs a very high H 2 O/ethylene oxide (EO) molar ratio of 20–25, leading to extremely huge energy consumption. Therefore, a number of catalysts were developed for the reaction under a low H 2 O/EO ratio, − such as zeolite cages, Cobalt-Salen complexes, single-crystalline zeolite, and so on. It was noted that the preparation of these catalysts was complex, where the use of metal was unavoidable, which hindered their practical applications.…”