Phase-Transfer Synthesis of Symmetrical and Unsymmetrical Dialkyl Trithiocarbonates

Functional RAFT agents for radical‐controlled polymerization: Quantitative synthesis of trithiocarbonates containing functional groups as RAFT agents using equivalent amount of CS2

“…In a typical experiment, CS 2 (5.25 mmol) was added to a solution of benzyl chloride (5.0 mmol) in DMF (5 mL), and to the resulting mixture was added K 2 CO 3 (5.0 mmol) at 25 C. The mixture was stirred at 40 C. The colorless mixture gradually changed to yellow solution. The reaction was monitored periodically by 1 H NMR spectroscopy. After the quantitative consumption of benzyl chloride was confirmed, the reaction was quenched by pouring into ice-water.…”

“…1 For another application, trithiocarbonate derivatives are focused as reversible addition-fragmentation chain transfer (RAFT) agent, which enables controlled free-radical polymerization of various vinyl monomers to afford polymers with narrow polydispersities and controlled molecular weights. Dibenzyl trithiocarbonate (DBTTC) can be applicable to welldefined polymers or block copolymers with styrene, alkyl acrylate, acrylic acid, alkyl acrylamide, or acrylonitrile.…”

An efficient one-pot access to trithiocarbonate-tethered peptidomimetics

“…For instance, they act as therapeutic agents such as inhibitors of histone deacetylases (HDAC) in the treatment of cancer, 4 and as pesticides and insecticides. 5 In organic synthesis, these compounds are employed as reversible addition fragmentation chain-transfer agents (RAFT) in radical polymerization 6 and as key precursors for the preparation of a number of compounds like trithiocarbonate-S-oxides, 7 thiols, 8 olefins, 9 thioacetates, 10 and derivatives of dicarbonyldithiocarboxylate. 11 They have also been employed as a protection for thiol functionality 12 and as useful compounds in the growing arsenal of nanotechnology in surface and colloidal science.…”

“…16 Other alternative routes for their synthesis include the reaction of sodium trithiocarbonates with epoxides, 17 reaction of metal xanthates with episulfides, 18 or the reaction of thiol with CS 2 in the presence of KOH under phase transfer catalyst to form potassium trithiocarbonate followed by subsequent reaction with an alkyl halide. 5 Wood et al reported the synthesis of symmetrical trithiocarbonates starting from primary thiols using 1,1 0 -thiocarbonyldiimidazole (TCDI). 6 Trithiocarbonates syntheses by S-arylation of potassium carbonotrithioates with diaryliodonium salts were developed by Wang et al 19 They have also been prepared by a one-pot reaction of alkyl halides with CS 2 in the presence of Cs 2 CO 3 , 20 KF/Al 2 O 3 , 21 or tetra-n-butylammonium hydroxide (TBAH).…”

“…According to established mechanism, the thiol and CS 2 react initially in the presence of TEA to generate a triethylamine salt of corresponding trithiocarbonate, which then react with alkyl halide to furnish the trithicarbonate compound. 5 Our primary targets were dipeptidomimetics of the type 4 (Scheme 1 and Table 1) which were accessed by employing a N-protected amino alkyl thiol, CS 2 , TEA and bromomethyl ester. The Fmoc/Z-protected amino alkyl thiols 1 were prepared according to the protocol recently reported by us.…”