- Controlled radical polymerization of acrylonitrile in the presence of trithiocarbonates as reversible addition-fragmentation chain transfer agents
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Specific features of pseudo-living radical polymerization of acrylonitrile in dimethyl sulfoxide solution in the presence of low-molecular-weight and polymeric trithiocarbonates as reversible addition-fragmentation chain transfer agents were studied.
- Chernikova,Poteryaeva,Belyaev,Sivtsov
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- Influence of the microstructure of acrylic acid-n-butyl acrylate copolymers prepared by pseudoliving radical polymerization by the reversible addition-fragmentation chain transfer mechanism on their surface activity in aqueous solutions
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The influence of the microstructure of acrylic acid-n-butyl acrylate copolymers prepared by pseudoliving radical polymerization by the reversible addition-fragmentation chain transfer mechanism on their surface activity in aqueous solutions was studied. The mechanisms of adsorption of polymer macromolecules on the phase boundary, accounting for the difference in the behavior of the random and block copolymers, were suggested. The dependence of the surface activity on the chain flexibility was elucidated. This dependence is very significant for the random copolymers and insignificant for the block copolymers.
- Sivtsov,Chernikova,Terpugova,Yasnogorodskaya
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- Selective one-pot synthesis of trithiocarbonates, xanthates, and dithiocarbamates for use in RAFT/MADIX living radical polymerizations
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We report a facile route for the production of chain transfer agents for reversible addition fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations, via a one-pot reaction. 1,1′-Thiocarbonyl diimidazole (TCDI) undergoes controlled monosubstitution when reacted with secondary thiols or alcohols. The intermediate S/O-esters of imidazole-N-thionocarboxylic acid react efficiently with a range of primary thiols, alcohols, and amines to form asymmetrical dithiocarbonates, trithiocarbonates, and dithiocarbamates, respectively. The synthesis provides a facile approach to the controlled radical polymerization of vinyl monomers through the reversible addition-fragmentation chain transfer (RAFT) mechanism.
- Wood, Murray R.,Duncalf, David J.,Rannard, Steven P.,Perrier, Sebastien
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- Thermoresponsive PS-b-PNIPAM-b-PS Micelles: Aggregation behavior, segmental dynamics, and thermal response
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We have studied the thermal behavior of amphiphilic, symmetric triblock copolymers having short, deuterated polystyrene (PS) end blocks and a large poly(N-isopropylacrylamide) (PNIPAM) middle block exhibiting a lower critical solution temperature (LCST) in aqueous solution. A wide range of concentrations (0.1-300 mg/mL) is investigated using a number of analytical methods such as fluorescence correlation spectroscopy (FCS), turbidimetry, dynamic light scattering (DLS), small-angle neutron scattering (SANS), and neutron spin-echo spectroscopy (NSE). The critical micelle concentration is determined using FCS to be 1 μM or less. The collapse of the micelles at the LCST is investigated using turbidimetry and DLS and shows a weak dependence on the degree of polymerization of the PNIPAM block, SANS with contrast matching allows us to reveal the core-shell structure of the micelles as well as their correlation as a function of temperature. The segmental dynamics of the PNIPAM shell are studied as a function of temperature and are found to be faster in the collapsed state than in the swollen state. The mode detected has a linear dispersion in q2 and is found to be faster in the collapsed state as compared to the swollen state. We attribute this result to the averaging over mobile and immobilized segments.
- Adelsberger, Joseph,Kulkami, Amit,Jain, Abhinav,Wang, Weinan,Bivigou-Koumba, Achille M.,Busch, Peter,Pipich, Vitaliy,Holderer, Olaf,Hellweg, Thomas,Laschewsky, Andre,Mueller-Buschbaum, Peter,Papadakis, Christine M.
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- Norbornene-containing dithiocarbamates for use in reversible addition-fragmentation chain transfer (RAFT) polymerization and ring-opening metathesis polymerization (ROMP)
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Two new dithiocarbamate chain transfer agents (CTAs) with norbornene-containing Z-groups were prepared for use in reversible addition-fragmentation chain transfer (RAFT) polymerization. CTA 1b, which contains an electron deficient norbornene imide Z-group, was found to effectively mediate RAFT polymerization of 2° more activated monomers (MAMs) but did not facilitate RAFT of 3° MAMs or less activated monomers (LAMs). In contrast, CTA 2, derived from a norbornene amine, was well suited for the polymerization of LAMs, but did not control RAFT of MAMs. Poly(vinyl acetate) (PVAc), prepared by RAFT polymerization mediated by CTA 2, possessed the expected CTA-derived α- and ω-end groups. Ring-opening metathesis polymerization (ROMP) of 2 was carried out, and full conversion to polymer was achieved within 20 min. Based on this result, ROMP grafting-through of a PVAc macromonomer derived from CTA 2 was carried out, resulting in the formation of a well-defined PVAc bottlebrush polymer with a narrow molecular weight distribution.
- Foster, Jeffrey C.,Radzinski, Scott C.,Lewis, Sally E.,Slutzker, Matthew B.,Matson, John B.
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- End group polarity and block symmetry effects on cloud point and hydrodynamic diameter of thermoresponsive block copolymers
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Thermoresponsive block copolymers are of interest for delivery vehicles in the body. Often an interior domain is designed for the active agent and the exterior domain provides stability in the bloodstream, and may carry a targeting ligand. There is still much to learn about how block sequence and chain end identity affect micelle structure, size, and cloud points. Here, hydrophilic oligo(ethylene glycol) methyl ether acrylate and more hydrophobic di(ethylene glycol) methyl ether methacrylate monomers were polymerized to give amphiphilic block copolymers with amphiphilic chain ends. The block sequence and chain end identity were both controlled by appropriate choice of RAFT chain transfer agents to study the effect of 'matched' and 'mismatched' chain end polarity with amphiphilic block sequence. The affect of matching or mismatching chain end polarity and block sequence was studied on the hydrodynamic diameter, cloud point, and temperature range of the chain collapse on linear di- and triblock copolymers and star diblock polymers. The affects of matching or mismatching chain end polarity were significant with linear diblock copolymers but more complex with triblock and star copolymers. Explanations of these results may help guide others in designing thermoresponsive block copolymers.
- Xiang, Xu,Ding, Xiaochu,Chen, Ning,Zhang, Beilu,Heiden, Patricia A.
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- Controlled (Co)polymerization of methacrylates using a novel symmetrical trithiocarbonate raft agent bearing diphenylmethyl groups
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Herein, we report a novel type of symmetrical trithiocarbonate chain transfer agent (CTA) based diphenylmethyl as R groups. The utilization of this CTA in the Reversible Addition-Fragmentation chain Transfer (RAFT) process reveals an efficient control in the polymerization of methacrylic monomers and the preparation of block copolymers. The latter are obtained by the (co)polymerization of styrene or butyl acrylate using a functionalized macro-CTA polymethyl methacrylate (PMMA) previously synthesized. Data show low molecular weight dispersity values (D 1.5) particularly in the polymerization of methacrylic monomers. Considering a typical RAFT mechanism, the leaving groups (R) from the fragmentation of CTA should be able to re-initiate the polymerization (formation of growth chains) allowing an efficient control of the process. Nevertheless, in the case of the polymerization of MMA in the presence of this symmetrical CTA, the polymerization process displays an atypical behavior that requires high [initiator]/[CTA] molar ratios for accessing predictable molecular weights without affecting the D. Some evidence suggests that this does not completely behave as a common RAFT agent as it is not completely consumed during the polymerization reaction, and it needs atypical high molar ratios [initiator]/[CTA] to be closer to the predicted molecular weight without affecting the D. This work demonstrates that MMA and other methacrylic monomers can be polymerized in a controlled way, and with “living” characteristics, using certain symmetrical trithiocarbonates.
- Enríquez-Medrano, Francisco Javier,Grana, Alvaro Leonel Robles,Maldonado-Textle, Hortensia,Olivares-Romero, José Luis,Thomas, Claude St,Torres-Lubián, José Román,Valencia, Luis,de León, Ramón Díaz
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- A convenient one-pot method for the synthesis of symmetrical dialkyl trithiocarbonates using NH4OAc under mild neutral conditions
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A facial, new, one-pot method for the preparation of symmetrical organic trithiocarbonates from various alkyl halides and carbon disulfide is described. This is a convenient, clean, and mild procedure, which involves the use of the neutral, nontoxic, commercially available, and inexpensive reagent NH4OAc in the preparation of the trithiocarbonate ion from carbon disulfide.
- Arzehgar, Zeinab,Ahmadi, Hosna
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p. 303 - 306
(2018/11/01)
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- Superbasic system CsOH/DMSO as a reagent for a fast one-step synthesis of symmetrical dialkyl trithiocarbonates
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Symmetrical dialkyl trithiocarbonates were readily synthesized in excellent yields by one-step reaction of carbon disulfide and various alkyl halides under mild reaction conditions in the presence of cesium hydroxide as a super basic system. This method provides a synthesis of symmetrical dialkyl trithiocarbonates in short reaction times without the use of highly toxic starting materials.
- Yousefi, Ali
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p. 672 - 677
(2015/11/18)
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- Investigations of the Thermal Responsiveness of 1,4,2-Oxathiazoles
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The first systematic study of the thermal rearrangement/fragmentation of 5,5-disubstituted 1,4,2-oxathiazoles into isothiocyanates is reported. Structure-activity relationships reveal that the choice of substituent at the 5-position of the 1,4,2-oxathiazoles is the predominant factor to influence the ease of fragmentation.
- Hewitt, Russell J.,Ong, Michelle Jui Hsien,Lim, Yi Wee,Burkett, Brendan A.
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supporting information
p. 6687 - 6700
(2015/10/29)
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- An efficient one-pot approach to the synthesis of symmetric trithiocarbonates from carbon disulfide and alkyl halides using imidazole
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A novel method is reported for the synthesis of symmetric dialkyl and cyclic (5, 6 and 7 member) trithiocarbonates from alkyl halides and carbon disulfide in the presence of imidazole and water in DMSO under mild reaction conditions. Imidazole is used as an inexpensive, non-toxic and readily available catalyst in this procedure.
- Soleiman-Beigi, Mohammad,Taherinia, Zahra
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p. 470 - 476
(2014/08/18)
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- 2,2,4,4-Tetrathio substituted 1,3-dithietanes
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The synthesis of 2,2,4,4-tetrathio substituted 1,3-dithietanes and their intermediates by reaction of thiophosgene with carbonotrithioates or O-ethyldithiocarbonate is reported. Their reactivity against thermolysis and aminolysis was investigated.
- Weber, Wolfgang,Chirowodza, Helen,Pasch, Harald
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p. 2017 - 2021
(2013/03/14)
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- K3PO4-mediated one-pot synthesis of symmetrical trithiocarbonates
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A new procedure has been developed for synthesis of symmetrical trithiocarbonates by one-pot reaction of carbon disulfide, and various alkyl halides in dimethylformamide using K3PO4 as an inexpensive and effective reagent.
- Movassagh, Barahman,Alapour, Saba
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p. 222 - 226
(2013/08/26)
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- POLYMER PARTICLES
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The present invention relates to a method of forming polymer on the surface of polymer particles, the method comprising: (i) providing a dispersion comprising a continuous aqueous phase, a dispersed organic phase comprising one or more ethylenically unsaturated monomers, and a RAFT agent as a stabiliser for said organic phase; (ii) polymerising the one or more ethylenically unsaturated monomers under the control of the RAFT agent to form an aqueous dispersion of seed polymer particles; (iii) crosslinking the seed polymer particles; (iv) swelling the crosslinked seed particles with one or more ethylenically unsaturated monomers to form an aqueous dispersion of monomer swollen crosslinked seed polymer particles; (v) increasing the temperature of the monomer swollen crosslinked seed polymer particles to expel at least some of the monomer therein onto the surface of the particles; and polymerising at least the expelled monomer to form polymer on the surface of the particles.
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- TBAH-catalyzed one-pot synthesis of symmetrical trithiocarbonates from alkyl halides and carbon disulfide under neat aqueous conditions
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A novel and efficient, tetra-n-butylammonium hydroxide catalyzed, one-pot protocol has been developed for the synthesis of symmetrical trithiocarbonates from alkyl halides and carbon disulfide under neat aqueous conditions. Georg Thieme Verlag Stuttgart - New York.
- Soleiman-Beigi, Mohammad,Arzehgar, Zeinab,Movassagh, Barahman
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experimental part
p. 392 - 394
(2010/04/05)
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- A novel one-step synthesis of symmetrical dialkyl trithiocarbonates in the presence of phase-transfer catalysis
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Symmetrical trithiocarbonates were directly obtained, in moderate to excellent isolated yields, by the reaction of various primary, secondary, allylic and benzylic halides or alkyl tosylates with a suspension of granulated KOH and alumina in CS2 under phase-transfer catalysis. In this manner, cyclic trithiocarbonates such as 1,3-dithiolane-2-thione can also be prepared without formation of any polymeric by-products.
- Kiasat, Ali Reza,Mehrjardi, Mehdi Fallah
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experimental part
p. 639 - 642
(2009/05/11)
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- Basic Al2O3 as an efficient heterogeneous reagent for the synthesis of symmerical dialkyl trithiocarbonates
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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. Copyright Taylor & Francis Group, LLC.
- Kiasat, Ali Reza,Kazemi, Foad,Savari, Ali
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p. 1057 - 1063
(2008/09/18)
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- An efficient, one-pot synthesis of trithiocarbonates from alcoholic tosylates using the Cs2CO3/CS2 system
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A single-step novel protocol for the preparation of symmetrical trithiocarbonates from a corresponding variety of primary, secondary, and tertiary alcoholic tosylates using the Cs2CO3/CS 2 system, was developed. This protocol is mild and more efficient than the reported methods.
- Chaturvedi, Devdutt,Mishra, Nisha,Chaturvedi, Amit K.,Mishra, Virendra
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experimental part
p. 1467 - 1470
(2009/12/03)
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- Triethylamine-catalyzed one-pot synthesis of trithiocarbonates from carbon disulfide, thiols, and alkyl halides in water
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Symmetrical and unsymmetrical trithiocarbonates were prepared by a simple and efficient one-pot reaction of thiols, carbon disulfide, and alkyl halides in the presence of triethylamine in water at room temperature.
- Movassagh, Barahman,Soleiman-Beigi, Mohammad
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experimental part
p. 927 - 930
(2009/09/06)
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- Facile one pot synthesis of a range of reversible addition-fragmentation chain transfer (RAFT) agents
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The application of a universal synthetic strategy for the high yielding and facile synthesis of a wide range of functional RAFT agents including trithiocarbonates, xanthates and dithiocarbamates is described. The Royal Society of Chemistry.
- Skey, Jared,O'Reilly, Rachel K.
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supporting information; experimental part
p. 4183 - 4185
(2009/03/11)
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- An efficient, one-pot synthesis of trithiocarbonates from the corresponding thiols using the Mitsunobu reagent
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A novel Mitsunobu-based protocol has been developed for the synthesis of a variety of symmetrical and unsymmetrical trithiocarbonates from primary, secondary and tertiary thiols using carbon disulfide, in good to excellent yields. This protocol is mild and efficient compared to other reported methods.
- Chaturvedi, Devdutt,Chaturvedi, Amit K.,Mishra, Nisha,Mishra, Virendra
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p. 4886 - 4888
(2008/09/21)
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- A facile KF/Al2O3-mediated, one-pot synthesis of symmetrical trithiocarbonates from alkyl halides and carbon disulfide
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A facile, efficient, and convenient method has been developed for the one-pot synthesis of symmetrical trithiocarbonates from carbon disulfide and various alkyl halides in the presence of KF/Al2O3 in DMF at room temperature. Copyright
- Movassagh, Barahman,Soleiman-Beigi, Mohammad,Nazari, Mohammad
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- Imparting nanoparticle function with size-controlled amphiphilic polymers
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Herein we report our method of water solubilization and subsequent functionalization of a variety of nanoparticle systems with amphiphilic polymers containing build-in "chemical handles". We have used these polymers, which have narrow polydispersity indices, to impart water solubility and chemical sensitivity toward targeted species (here: pH). These material systems have high chemical conjugation efficiencies in aqueous conditions which may be used to create a variety of chemical and biological multifunctional materials. Copyright
- Chen, Yingchuan,Thakar, Rahul,Snee, Preston T.
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p. 3744 - 3745
(2008/09/20)
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- Mild and efficient one-step synthesis of trithiocarbonates using minimum amount of CS2
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Symmetrical dialkyl trithiocarbonates were obtained from various alkyl halides with an equivalent of carbon disulfide and cesium carbonate in polar aprotic solvents, although the conventional synthesis of trithiocarbonates had required large excess amount of carbon disulfide. This reaction proceeds under ambient conditions, for example, at room temperature under an aerial atmosphere, without strong base nor phase-transfer catalyst. Georg Thieme Verlag Stuttgart.
- Aoyagi, Naoto,Ochiai, Bungo,Mori, Hideharu,Endo, Takeshi
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p. 636 - 638
(2007/10/03)
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- Synthesis of Symmetrical Dialkyl Trithiocarbonates Using a Polymer Supported System
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Symmetrical dialkyl trithiocarbonates were readily snythesized in excellent yields from alkyl halides and carbon disulfide under mild reaction condition in the presence of a regenerable hydroxide form of an anion exchange resin.
- Tamami, Bahman,Kiasat
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p. 454 - 455
(2007/10/03)
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- A Novel One-step Synthesis of Symmetrical Dialkyl Trithiocarbonates
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Symmetrical dialkyl trithiocarbonates were obtained directly, in excellent yields, by reaction of primary or secondary alkyl, benzyl or allyl halides with KOH and carbon disulfide in anhydrous THF; compounds such as methyl 4-bromomethylbenzoate and chloromethyl methyl ether can also be tolerated under the reaction conditions to provide trithiocarbonates 6 and 9 in acceptable yields.
- Leung, Man-kit,Hsieh, Dung-Ting,Lee, Kang-Hwa,Liou, Jia-Chie
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p. 478 - 479
(2007/10/03)
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- ONE POT PHASE TRANSFER SYNTHESIS OF TRITHIOCARBONATES FROM CARBON DISULPHIDE AND ALKYL HALIDES
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Symmetrical and cyclic alkyl trithiocarbonates were synthesized by reacting CS2 and 33percent aqueous NaOH with alkyl halides under phase transfer catalysis conditions
- Lee, Albert W. M.,Chan, W. H.,Wong, H. C.
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p. 1531 - 1536
(2007/10/02)
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- Phase-Transfer Synthesis of Symmetrical and Unsymmetrical Dialkyl Trithiocarbonates
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Symmetrical and unsymmetrical dialkyl trithiocarbonates having the formula R1S-CS-SR2 (wherein R1 = or R2) were prepared under phase-transfer catalytic conditions by one-pot reactions involving carbon disulfide, sodium sulfide, alkyl halides and alkyl mercaptans.
- Degani, Iacopo,Fochi, Rita,Gatti, Antonella,Regondi, Valeria
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p. 894 - 899
(2007/10/02)
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- Some Reactions of Trichloromethanesulfenyl Chloride with Alcohols and Thiols
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Four new trichloromethyl disulfides, four alkyl orthocarbonates, and two trithiocarbonates have been synthesized and have been characterized by physical, spectral, and analytical properties.
- Islam, Nafisa B.,Kwart, Harold,Khan, S.
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p. 509 - 512
(2007/10/02)
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- Applications of Phase Transfer Catalysis, 26. - Thioureas by Three-Component Reactions of Amines, Carbon Tetrachloride, and Sulfide Ions
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The title reactions proceed exothermically in the presence of a phase transfer catalyst.Thiophosgene is an intermediate in this conversion, and its phase transfer catalytic transformation into carbon disulfide and trithiocarbonate can be demonstrated.Perchloromethanethiol/sodium sulfide and a PT catalyst yield thiophosgene too.Activated vicinal dibromides were debrominated by Na2S/catalyst.
- Broda, Witold,Dehmlow, Eckehard V.
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p. 1839 - 1843
(2007/10/02)
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- Pesticidal compositions containing phosphoric esters and divalent sulphur compounds
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Pesticidal composition comprising: a pesticidal, phosphoric ester the molecule of which has at least one alkyl group of 1 to 3 carbon atoms, 0.05 to 10% of an agent stabilizing the said ester against decomposition by protonisation, together with adjuvants characterized in that the stabilizing agent comprises at least one sulphur compound containing per molecule at least one divalent sulphur atom of which one valence is bonded to an atom chosen from sulphur, carbon, nitrogen, hydrogen, and metals capable of giving a salt, the other valence being bonded to an atom chosen from hydrogen, the carbon atom already noted, a second carbon atom, the nitrogen atom already noted, a second nitrogen atom, the metal atom already noted in the case of a metal of valence greater than one, a second atom of metal and oxygen when the first valence is not attached to an atom of hydrogen, the proportion of sulphur calculated with reference to the weight of the sulphur compound being between 5 and 99%. Process for stabilizing a phosphoric ester of which the molecule possesses at least one alkyl group containing 1 to 3 carbon atoms characterized in that there is added to the phosphoric ester or to a mixture which contains it, 0.05 to 10% calculated on the weight of the phosphoric acid ester of an agent capable of stabilizing the said phosphoric ester against protonisation and comprising at least one sulphur compound such as that defined thereupon.
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