This paper presents a review of living radical polymerization achieved with thiocarbonylthio compounds [ZC(=S)SR] by a mechanism of reversible addition–fragmentation chain transfer (RAFT). Since we first introduced the technique in 1998, the number of papers and patents on the RAFT process has increased exponentially as the technique has proved to be one of the most versatile for the provision of polymers of well defined architecture. The factors influencing the effectiveness of RAFT agents and outcome of RAFT polymerization are detailed. With this insight, guidelines are presented on how to conduct RAFT and choose RAFT agents to achieve particular structures. A survey is provided of the current scope and applications of the RAFT process in the synthesis of well defined homo-, gradient, diblock, triblock, and star polymers, as well as more complex architectures including microgels and polymer brushes.

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Living radical polymerization by the RAFT process

This paper provides a third update to the review of reversible deactivation radical polymerization (RDRP) achieved with thiocarbonylthio compounds (ZC(=S)SR) by a mechanism of reversible addition-fragmentation chain transfer (RAFT) that was published in June 2005 (Aust. J. Chem. 2005, 58, 379). The first update was published in November 2006 (Aust. J. Chem. 2006, 59, 669) and the second in December 2009 (Aust. J. Chem. 2009, 62, 1402). This review cites over 700 publications that appeared during the period mid 2009 to early 2012 covering various aspects of RAFT polymerization which include reagent synthesis and properties, kinetics and mechanism of polymerization, novel polymer syntheses, and a diverse range of applications. This period has witnessed further significant developments, particularly in the areas of novel RAFT agents, techniques for end-group transformation, the production of micro/nanoparticles and modified surfaces, and biopolymer conjugates both for therapeutic and diagnostic applications.

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Living Radical Polymerization by the RAFT Process - A Second Update

Tetrathiafulvalenes, oligoacenenes, and their buckminsterfullerene derivatives: the brick and mortar of organic electronics.

Radical addition-fragmentation chemistry in polymer synthesis

Among the living radical polymerization techniques, reversible addition–fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations appear to be the most versatile processes in terms of the reaction conditions, the variety of monomers for which polymerization can be controlled, tolerance to functionalities, and the range of polymeric architectures that can be produced. This review highlights the progress made in RAFT/MADIX polymerization since the first report in 1998. It addresses, in turn, the mechanism and kinetics of the process, examines the various components of the system, including the synthesis paths of the thiocarbonyl-thio compounds used as chain-transfer agents, and the conditions of polymerization, and gives an account of the wide range of monomers that have been successfully polymerized to date, as well as the various polymeric architectures that have been produced. In the last section, this review describes the future challenges that the process will face and shows its opening to a wider scientific community as a synthetic tool for the production of functional macromolecules and materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:5347–5393, 2005

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/pola.20986

Macromolecular design via réversible addition-fragmentation chain transfer (RAFT)/Xanthates (MADIX) polymerization

Product isotope effects (p.i.e.), given by the product ratio RH : RD obtained in 1 : 1 MeOH–MeOD, have been determined for cleavages of some substituted benzyltrimethylsilanes by methanolic sodium methoxide; values (with estimated uncertainties of ±20%) given in the sequence of decreasing ease of cleavage, are: (X or XY in XC6H4– or XYC6H3CH2–SiMe3)p-NO2, 2-Me-4-NO2, or o-NO2, 10 (25 °C); p-COPh, 7 (50 °C); p-SO2Ph, 2.9 (50 °C); 2-Me-6-NO2, 10 (25 °C); p-CN, 2.0 (50 °C); 3,5-Cl2, 1.3 (50 °C); m-NO2, 1.3 (25 °C); m-CN, m-CF3, or H, 1.2 (50 °C). These values are believed to represent the kinetic isotope effects for interactions of the carbanions R– with MeOH and MeOD; as expected, except when there is unusual steric hindrance, they show an overall increase with increasing reactivity of the RSiMe3 compound, and thus with the pKa of the carbon acid RH, but remain effectively constant over a large pKa range before increasing steeply over a small pKa range. The p.i.e. values (at 50 °C) for the compounds Ph2CHSiMe3 and Ph3CSiMe3 have been redetermined, and found to be ca. 1.3 ± 0.2, consistent with the values for substituted benzyl compounds of comparable reactivity. The value for the triphenyl compound is incompatible with a reported value of the kinetic isotope effect for proton abstraction from triphenylmethane by sodium methoxide in methanol.

Further studies of solvent isotope effects in the cleavage of substituted benzyltrimethylsilanes by methanolic sodium methoxide. Intermediate kinetic isotope effects for reactions of carbanions with methanol

Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

On the Reactivity of Ferrocenoylsilanes

The antioxidant activity of five phenols, i.e. catechol, homovanillyl alcohol, homovanillic acid, gallic acid and syringic acid, present in all olive oils has been investigated. For gallic acid and syringic acid the Bond Dissociation Enthalpy BDE(O-H) has been determined through the EPR (Electron Paramagnetic Resonance spectroscopy) based on radical equilibration technique as 81.0 and 82.1 kcal mol −1 , respectively. For both homovanillyl alcohol and homovanillic acid the BDE(O-H) values were assumed to be identical to that of the similar 2-methoxy-4-methylphenol (82.8 kcal mol −1 ). The inhibition rate constants of the above compounds and of catechol in the autoxidation of cumene (or styrene) were also determined in acetonitrile/chlorobenzene solution and corrected for hydrogen bonding by acetonitrile. The results indicate that in organic solvents gallic acid and catechol are fairly good antioxidants, while homovanillyl alcohol, homovanillic acid and syringic acid, i.e. the three 2-methoxy substituted de...

Dante Macciantelli

Papers

Further studies of solvent isotope effects in the cleavage of substituted benzyltrimethylsilanes by methanolic sodium methoxide. Intermediate kinetic isotope effects for reactions of carbanions with methanol

Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

On the Reactivity of Ferrocenoylsilanes

Antioxidant activity of some simple phenols present in olive oil.

Conformational studies by dynamic nmr. Part 18. Restricted rotation in nitrosobenzene and phenylhydrazine