Cyclic Trithiocarbonate Research Articles

Development of Ring-Expansion RAFT Polymerization of tert-Butyl Acrylate with a Cyclic Trithiocarbonate Derivative toward the Facile Synthesis of Cyclic Polymers.

Polymers with cyclic topology have no terminal structure and, therefore, exhibit various unique physical and functional properties compared to those of linear analogs. In this paper, we report an innovative methodology for the synthesis of cyclic polymers via ring-expansion RAFT (RE-RAFT) polymerization of vinyl monomers using a cyclic trithiocarbonate derivative (CTTC) as a RAFT agent. RE-RAFT of tert-butyl acrylate (TBA) was performed to yield a mixture of polymers exhibiting a bimodal size exclusion chromatography (SEC) trace. Both the peak top molecular weights shifted to higher-molecular-weight regions as the monomer conversion increased. The structure of the resulting polymer mixture was examined by 1H NMR and MALDI-TOF-MS. Detailed studies indicated that the obtained polymer of higher molecular weight was one of the large-sized cyclic polymers generated by the fusion of smaller-sized cyclic polymers during the RE-RAFT polymerization process. This approach opens the door to the simple synthesis of well-controlled cyclic polymers with complex structures, such as alternating and multi-block repeat unit sequences.

Poly(thiourethane-co-ethylene oxide) networks crosslinked with disulfide bonds: Reinforcement with POSS and use for recyclable solid polymer electrolytes

In this contribution, we reported the synthesis of the solid polymer electrolytes (SPEs) involving poly(thiourethane-co-ethylene oxide) [denoted P(TU-EO)] and lithium bis(trifluorosulfonyl)imide (LiTFSI). The SPEs were the networks crosslinked with disulfide bonds. First, a linear multi-segmented poly(mercaptothiourethane-co-ethylene oxide) copolymer [denoted P(MTU-EO)] was synthesized via the step-growth polymerization of a difunctional five-membered cyclic trithiocarbonate (D5CT) with equimolar α,ω-diamino-terminated poly(ethylene oxide). Thereafter, the crosslinking of the multi-segmented copolymer was carried out via the radical coupling reaction of thiol groups and the disulfide bonds acted as the crosslinkages. To reinforce the network, octavinyl POSS was introduced and the additional crosslinking was generated via the thiol-ene addition reaction between thiol groups of P(MTU-EO) and vinyl groups of the POSS macromer. It was found that the crosslinking densities increased with increasing the incorporation of POSS. The LiTFSI salt can be well dispersed into the P(TU-EO)-POSS networks and the crystallization of PEO was effectively suppressed. Depending on the molar ratio of ethylene oxide to LiTFSI and the percentage of POSS, the ionic conductivity of the SPEs can reach 2.1 × 10−5 S × cm−1 at 300 K. More importantly, the SPEs can be reprocessed (or recycled) via the dynamic exchange of disulfide bonds.

Development of an Adhesive Gel System for Changing the Structure and Properties of Its Adhesive Joint via Reactions with Amine Molecules after Adhesion.

Adhesive gel systems are attracting increasing interest from researchers to use gel materials for artificial biomaterials and engineering materials. Humans, among other living beings, eat foods, get nutrients from them, and use these nutrients to grow up day by day. The shapes and characteristics of their bodies change depending on the nutrients they get. This research develops an adhesive gel system that the chemical structure of the adhesive joint and their properties can be changed and regulated after adhesion, like the growth of living beings. The adhesive joint, which is constructed using a linear polymer comprising a cyclic trithiocarbonate monomer and acrylamide, developed in this research reacts with amines and forms chemical structures depending on amines. The differences in chemical structures endow the adhesive joint with the characteristics and properties that depend on the reaction of amines with the adhesive joint.

Polythiourethanes Crosslinked with Dynamic Disulfide Bonds: Synthesis via Nonisocyanate Approach, Thermomechanical and Reprocessing Properties.

Polythiourethanes (PTUs) crosslinked with dynamic disulfide bonds are synthesized via a nonisocyanate approach. First, a difunctional five-membered cyclic trithiocarbonate (1) is synthesized via the reaction of diglycidyl ether of bisphenol A (DGEBA) with carbon disulfide (CS2 ). Thereafter, the step-growth polymerizations of 1 with α,ω-diamino poly(propylene oxide)s with various molar masses are carried out to obtain a series of linear poly(mercapto thiourethane)s. These linear poly(mercapto thiourethane)s are readily crosslinked upon formation of disulfide bonds, which are generated via radical coupling reaction with the side mercapto groups. These crosslinked PTUs can be tailored into the materials from thermosetting plastics to crosslinked elastomers, depending on the molar masses of α,ω-diamino poly(propylene oxide)s. More importantly, these crosslinked PTUs display excellent reprocessing properties at elevated temperatures, which is attributable to the metathesis reaction of dynamic disulfide bonds.

Synthesis and fundamental properties of methacrylate polymer containing five‐membered cyclic trithiocarbonate group

Abstract4‐(1,3‐Dithia‐2‐thioxocyclopenthyl)methacrylate (TCMA), containing the five‐membered trithiocarbonate moiety, was prepared from glycidyl methacrylate (GMA) through 2,3‐epithiopropyl methacrylate (ETMA). At first step, GMA was converted to ETMA by the reaction using thiourea. At second step, ETMA was reacted efficiently with carbon disulfide in the presence of a catalytic amount of 1,2‐dimethyltetrahydropyrimidine to give TCMA. The polymerization of TCMA proceeded under standard radical conditions to give the polymeric TCMA in 94% yield. The copolymerizations of TCMA with ethyl acrylate (EA) or acrylonitrile (AN) were conducted by changing the feed molar ratios of the monomers, in which the corresponding copolymers were obtained in over 83% yields. In addition, the obtained polymers showed the high values of refractive index over ca. 1.6 due to the presence of the cyclic trithiocarbonate structure.

Synthesis of aliphatic polymers with high refractive index by photoinduced polyaddition of thiols to bifunctional allyl monomer containing tetrathiaspiro structure

Zinc chloride effectively catalyzed the reaction of allyl-substituted episulfide and cyclic trithiocarbonate to obtain the corresponding bisallyl monomer containing tetrathiaspiro ring in high yield. The homogeneous mixture of the bisallyl monomer, multifunctional thiols, and a catalytic amount of photo-radical initiator undergoes a photoinduced thiol–ene reaction to result in cross-linked films. Thus the films obtained in this way, although they are aliphatic polymers containing neither aromatic ring nor halogen atom, have a high refractive index (nD25) of around 1.63. Figure S1. UV spectra of 2 and M1 in CH3CN (10 mg/L, respectively). Table S1. Refractive indices of P1 and P2 at different wavelengths. Figure S2.1H NMR spectrum (400 MHz) of a solution of M1 in CDCl3 at 25 °C. Figure S3.13C NMR spectrum (100 MHz) of a solution of M1 in CDCl3 at 25 °C. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

ChemInform Abstract: Synthesis of Dithiocarbamates Containing Disulfide Linkage Using Cyclic Trithiocarbonate and Amines under Solvent‐Catalyst Free Condition.

A green and facile synthesis of dithiocarbamate derivatives containing disulfide linkage by the ring opening reaction of trithiocarbonate with amines under solvent and catalyst-free condition with excellent yields is being reported. Environmental benignity, easy work up, smaller reaction time, and lack of column chromatography are the significant features of this protocol. The cyclic trithiocarbonate (1) has been used as a starting material for the first time to synthesize compounds of biological interest (3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n, 3o, 3p, 3q).

Trans‐1,2‐Cyclohexanedisulfonic Acid: An Optically Active Linker for Coordination Polymers

AbstractRacemic 1,2‐cyclohexanedisulfonic acid was prepared from cyclohexene oxide via the cyclic trithiocarbonate and isolated as its barium salt. Optical resolution was achieved by crystallization with (–)‐(R,R)‐1,2‐cyclohexane diamine; the absolute configuration was established by X‐ray crystallography of this salt, [C6H10(NH3)2][C6H10(SO3)2]. Solid‐state structures were investigated of the racemic acidic sodium disulfonate Na(H5O2)[C6H10(SO3)2] and the optically active disulfonates Na2[C6H10(SO3)2]·1.8H2O and Ag(NH2Me2)[C6H10(SO3)2].

Synthesis of Dithiocarbamates Containing Disulfide Linkage Using Cyclic Trithiocarbonate and Amines under Solvent–Catalyst Free Condition

A green and facile synthesis of dithiocarbamate derivatives containing disulfide linkage by the ring opening reaction of trithiocarbonate with amines under solvent and catalyst‐free condition with excellent yields is being reported. Environmental benignity, easy work up, smaller reaction time, and lack of column chromatography are the significant features of this protocol. The cyclic trithiocarbonate (1) has been used as a starting material for the first time to synthesize compounds of biological interest (3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n, 3o, 3p, 3q).

One-pot self-coupling concurrent living polymerizations of inimers to synthesize hyperbranched-linking-hyperbranched polymer cylinders via cyclic trithiocarbonate

In this paper, we present a convenient one-pot self-coupling concurrent living polymerization strategy for synthesizing one-dimensional hyperbranched-linking-hyperbranched cylindrical macromolecules. A RAFT agent served as a “hyper-linker” to link hyperbranched blocks. The obtained polymers showed high regularity of long-range order evidenced by small angle X-ray diffraction patterns and the lyotropic liquid crystalline phase. The formation mechanism of the hyperbranched-linking-hyperbranched structures and the role of the RAFT agents were investigated.

Synthesis and micelle behavior of (PNIPAm-PtBA-PNIPAm)m amphiphilic multiblock copolymer

A linear amphiphilic multiblock copolymer (PNIPAm-PtBA-PNIPAm)m was successfully synthesized by a two-step reversible addition–fragmentation transfer (RAFT) polymerization in the presence of a cyclic trithiocarbonate as RAFT agent. The micelle behavior of (PNIPAm-PtBA-PNIPAm)m multiblock copolymer in aqueous solution was then investigated by means of normal TEM, cryo-TEM, static and dynamic light scattering. The morphology, size, and size distribution of (PNIPAm-PtBA-PNIPAm)m micelles were found to be dependent on the initial concentration of multiblock copolymer in THF. Spherical micelles, associated aggregates of spherical micelles, cage-like micelles, layered structures, and vesicular micelles were experimentally observed, which were in good agreement with the prediction of theory and simulations on linear amphiphilic multiblock copolymer in selective solvent. The (PNIPAm-PtBA-PNIPAm)m micelles also exhibit thermo-sensitive behavior in aqueous solution because of the PNIPAm blocks.

One‐pot synthesis of well‐defined multiblock polymer: Combination of ATRP and RAFT polymerization involving cyclic trithiocarbonate

AbstractMultiblock polymers were prepared by combination of ATRP (CuBr/tris[(2‐pyridyl)methyl]amine) and RAFT polymerization involving cyclic trithiocarbonate (CTTC). In the combined polymerization system, the ATRP was introduced as constant radical source, CTTC underwent ring‐opening polymerization, and the incorporated trithiocarbonate moieties derived from CTTCs performed as RAFT agent. Through the integrated process, multiblock polymers containing predictable average block number together with controlled molecular weight of the blocks were prepared by one‐pot polymerization. The average block number of polymer was controlled by concentration ratio of CTTC to alkyl halide in ARTP, and the molecular weight of block were well regulated by concentration of CTTC and monomer conversion. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2425–2429, 2010

Basic Al2O3 as an Efficient Heterogeneous Reagent for the Synthesis of Symmerical Dialkyl Trithiocarbonates

This work deals with reaction of alkyl halides with carbon disulfide in the presence of basic alumina as heterogeneous and reusable reagent. It afforded symmetrical dialkyl trithiocarbonate in moderate to excellent isolated yields. Reaction of 1,2‐dichloro ethane with carbon disulfide also proceeded in a similar manner to give a five‐membered cyclic trithiocarbonate without formation of any polymeric by‐product.

Multiblock poly(4‐vinylpyridine) and its copolymer prepared with cyclic trithiocarbonate as a reversible addition–fragmentation transfer agent

AbstractThe polymerization of 4‐vinylpyridine was conducted in the presence of a cyclic trithiocarbonate (4,7‐diphenyl‐[1,3]dithiepane‐2‐thione) as a reversible addition–fragmentation transfer (RAFT) polymerization agent, and a multiblock polymer with narrow‐polydispersity blocks was prepared. Two kinds of multiblock copolymers of styrene and 4‐vinylpyridine, that is, (ABA)n multi‐triblock copolymers with polystyrene or poly(4‐vinylpyridine) as the outer blocks, were prepared with multiblock polystyrene or poly(4‐vinylpyridine) as a macro‐RAFT agent, respectively. GPC data for the original polymers and polymers cleaved by amine demonstrated the successful synthesis of amphiphilic multiblock copolymers of styrene and 4‐vinylpyridine via two‐step polymerization. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2617–2623, 2007

Controlled free-radical polymerization of methyl acrylate in the presence of a cyclic trithiocarbonate under γ-ray irradiation at low temperature

Controlled radical polymerization of MA has been achieved in the presence of a cyclic trithiocarbonate, 1,5-dihydro-2,4-benzodiehiepine-3-thione, under γ-ray irradiation (60 Gy/min) at low temperature. The narrow molecular weight distributions and the linear kinetics curve indicate that the polymerization is a controlled free-radical process at low temperature (especially at −76 °C). The structures of resultant polymers were characterized by matrix assisted laser desorption/ionization time-of-flight mass spectrometry, and the results show that cyclic polymers can be formed at −76 °C, which may result from the reduced diffusion rate and the suppressed chain-transfer reaction at the lower temperature. It is further evidenced that the good control of the polymerization at the lower temperature may be associated with the suppressed chain-transfer reaction, not like reversible addition-fragmentation transfer polymerization. The linear polymers probably result from the polymer chain radicals reacting with the radicals produced by the interaction of the irradiation and the monomer.

1,3-Dipolar cycloadditions of diphenyldiazomethane to thioketones: Rate measurements disclose thiones to be superdipolarophiles

1,3-Dipolar cycloadditions of diphenyldiazomethane to thioketones afford 2,5-dihydro-1,3,4-thiadiazoles 8, which rapidly lose N2. The liberated thiocarbonyl ylides 10 furnish thiiranes 9 by electrocyclic ring closure. The rate constants, measured by spectrophotometry (DMF, 40°C) for 16 cycloaliphatic and aromatic thioketones and one cyclic trithiocarbonate, stretch over five powers of 10 with fluorene-9-thione at the top and 2,2,5,5-tetramethylcyclopentanethione at the bottom. Electron-releasing substituents decrease the cycloaddition rate of thiobenzophenone; thus, the ambiphilic diphenyldiazomethane reacts as nucleophilic partner with the electrophilic thioketone. The influence of substituents and ring size on the reactivity of cycloalkanethiones, which are sterically hindered by two gem-dimethyl groups, will be discussed. Compared with electron-deficient CC and CC bonds, thiones are superdipolarophiles. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:433–442, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20262

Synthesis of Multiblock Polymer Containing Narrow Polydispersity Blocks

AbstractSummary: We have developed a new strategy to prepare multiblock polymers and copolymers via one‐ or two‐step polymerization using a polymerizable cyclic trithiocarbonate (CTTC), 4,7‐diphenyl‐[1,3]dithiepane‐2‐thione. CTTC undergoes ring‐opening process to incorporate a trithiocarbonate moiety. The trithiocarbonate moiety in turn, functions as a reversible addition fragmentation chain transfer (RAFT) agent. Through this mechanism, multiblock polystyrenes and polystyrene‐block‐ poly(butyl acrylate) copolymers containing various narrow polydispersity blocks can be prepared.Integrated process of ring‐opening and RAFT polymerizations involving cyclic trithiocarbonates.magnified imageIntegrated process of ring‐opening and RAFT polymerizations involving cyclic trithiocarbonates.

Styrene Polymerization in the Presence of Cyclic Trithiocarbonate

The cyclic trithiocarbonate 1,5-dihydrobenzo[e][1,3]diehiepine-3-thione was synthesized by two different methods: dialkylation of trithiocarbonate anion with alkyl halides in a two-phase system using an onium salt as a phase-transfer agent and reaction between carbon disulfide and alkyl halides using a commercially available hydroxide form of an anion-exchange resin. Styrene polymerization was carried out in the presence of cyclic trithiocarbonate. The molecular weights of polymers before and after treatment with diamine were quite different, and they increased linearly with the polymerization time, while the molecular weight distribution of all polymers obtained with the cyclic trithiocarbonate were broad as compared with the current RAFT agent. It is proposed that polystyrenes prepared in the presence of the cyclic trithiocarbonate have multiblock structure with more than one trithiocarbonate function per chain, and the cyclic trithiocarbonate functions rather than comonomer since it keeps the merit of...

Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions

Thieno[2,3-d]-1,2,3-thiadiazoles (1) react with carbon disulfide in a "Matryoshka-type" double compartment autoclave [1] to yield thieno[2,3-d]-1,3-dithiol-2-thiones (2). With BH3/Me2S the cyclic trithiocarbonate (2d) is cleaved and the product characterized after methylation as 4b. Compounds 7a and 7b are prepared via the thieno[2,3-d]-1,3-dithiolium salts (6) followed by NaBH4-reduction.

First preparative biocatalytic hydrolysis and S-methylation of cyclic trithiocarbonates

The biocatalytic degradation of a cyclic trithiocarbonate, 6-amino-5-methoxycarbonyl-thieno[2,3- d]-1,3-dithiole-2-thione 1 , is reported. The product of the hydrolysis of the five-membered ring by Pseudomonas chlororaphis ATCC 9447 oxidatively dimerized to form the tetrathiocin derivative 2 . Furthermore, we performed the first preparative biocatalytic methylation of an unnatural compound employing Emericella unguis ATCC 10032 by cleaving the dithiole ring 1 followed by methylation of both thiol groups to form the methylated product 4 in 64% isolated yield.