Functional Polythioamides Derived from Thiocarbonyl Fluoride**

Abstract

Polythioamide is a unique type of sulfur‐containing polymer with advanced functionalities. Nonetheless, the elemental sulfur commonly used in their synthesis tends to react readily with unsaturated functional groups, thereby limiting the scope of eligible substrates. Inspired by the highly efficient sulfur‐fluoride exchange (SuFEx) polymerization through discrete hubs, we present herein a pioneering and versatile approach to the synthesis of polythioamides from diboronic acids, secondary diamines, and thiocarbonyl fluoride as the central connective hub. Well‐defined structures, including previously inaccessible unsaturated substrates, were realized. These newly devised polythioamides can efficiently and selectively bind to metal ions and were applied in precious‐metal recovery. Further development resulted in PdII‐crosslinked single‐chain nanoparticles serving as recyclable homogeneous catalysts, thus demonstrating the vast potential of these unprecedented polythioamides. We anticipate that thiocarbonyl fluoride could emerge as a potent hub for facilitating the intricate synthesis of sulfur‐containing polymers.

Iterative SuFEx approach for sequence-regulated oligosulfates and its extension to periodic copolymers

“…In particular, polysulfates have been prepared through the step-growth polycondensation reactions between bis(aryl fluorosulfates) and silyl-protected diol monomers to give homo- and alternating copolymers (Fig. 1b ) 37 , 38 , 40 , 44 . More recently, a chain-growth polycondensation method has been reported to furnish block copolymer structures 45 .…”

“…Since 2014, there has been significant progress on the use of SuFEx chemistry to create new polymers, including polysulfates, polysulfamides, and polysulfluoridoimidates [37][38][39][40][41][42][43][44] . In particular, polysulfates have been prepared through the step-growth polycondensation reactions between bis(aryl fluorosulfates) and silyl-protected diol monomers to give homo-and alternating copolymers (Fig.…”

Thionation of poly(2-ethyl-2-oxazoline) and its effect on solubility and cloud point

“…[45][46][47] For the synthesis of polythioamides, multicomponent reactions involving elemental sulfur are mostly being used for the polymers which can be synthesized via polycondensation reactions. [48][49][50][51][52] However, very early attempts for accessing the thio-analogues of water-soluble polymers can be found in the literature with limited characterization, in particular for poly(N-vinylpyrrolidone) 53,54 and poly(Nvinylcaprolactam). 55 Another interesting feature of thioamides is that their sulfur lone pairs are weaker hydrogen bond acceptors relative to oxygen lone pairs in amides.…”

Multicomponent Polymerization of Sulfur, Diynes, and Aromatic Diamines and Facile Tuning of Polymer Backbone Structures

“…Sulfur-containing polymers including polysulfides, , polydisulfides, , polysulfones, polythiophenes, − polythioureas, and polythioamides are a group of popular advanced functional materials, , owing to their high refractive indices, − dielectric property, , dynamic covalent bond, crystallinity, and reprocessability. , Polythioamides, regarded as the analogues of traditional polyamide materials with oxygen atoms being replaced by sulfur atoms, have attracted much attention recently, because of their improved solubility and processability, weaker hydrogen bonding compared with their engineering plastics analogues, strong metal ion coordination abilities that enabled heavy metal ion absorption of mercury, platinum, palladium, and gold from aqueous solution, − and high light refractivity enabling potential application in optoelectronics . However, the preparation of polythioamides was reported usually by polycondensations with highly reactive sulfur-containing bifunctional monomers including dithioesters, dithioamides, and tetrathioterephthalates, with the release of harmful and toxic byproducts such as methanethiol. − Postmodification of polyamide using Lawesson’s reagent was another approach to prepare polythioamides but normally suffered from incomplete conversion, hydrolytic degradation, and solubility issue of polyamides …”