Five metal dithiocarbamate complexes [M(PTHIQDTC)] [where PTHIQDTC is (S)-1-phenyl-1,2,3,4-tetrahydroisoquinoline dithiocarbamate anion and M is Ni(II) (1), Sn(II) (2), Hg(II) (3), Pb(II) (4) and Zn(II) (5)] were synthesized from the reaction of MX (X is Cl for 1-3 and OAc for 4-5) with ligand of triethylammonium (S)-1-phenyl-1,2,3,4-tetrahydroisoquinoline dithiocarbamate [EtNH][PTHIQDTC] in methanolic solution at room temperature. The five complexes were characterized by IR, H andC NMR, mass spectrometry, elemental analysis and TGA analysis. Recrystallization of [Zn(PTHIQDTC)] (5) in dimethylsulfoxide (DMSO) converts 5 to [Zn(PTHIQDTC)(DMSO)] (6).
View Article and Find Full Text PDFNovel bis(nitroepoxides) were prepared based on terephthaldehyde and isophthaladehyde and their reactions with diversities of nucleophiles such as primary and secondary amine-based dithiocarbamic acids, xanthates, and ammonia-based dithiocarbmamates were investigated for the synthesis of bis(thiazolidine-2-thiones), bis(dithiocarbamates), bis(xanthates) and bis(thiazoles), respectively. It provides simple access to complex molecules in one step in high to excellent yields.
View Article and Find Full Text PDFBromonitroalkenes are useful molecules in synthetic organic chemistry. They are mainly prepared from nitroalkenes bromination reactions. In this review, the application of bromonitroalkenes as partners in the reaction with a diversity of mono- and bi-functional molecules, including aldehydes and ketones, active methylene compounds, 1,2-dicarbonyls, enamines, enols, electron-rich arenes, amidines, azomethine ylides, azirines, diazo compounds, and many others, is reviewed.
View Article and Find Full Text PDFCatalyst-free Markovnikov-selective hydrothiolation of unactivated alkenes still remains a great challenge. Herein, we develop a catalyst/metal/solvent-free methodology for the Markovnikov hydrothiolation of unactivated alkenes with in situ prepared dithiocarbamic acids, providing a wide array of alkyl dithiocarbamates. A variety of terminal, internal, cyclic, and acyclic unactivated alkenes were applied successfully in this protocol.
View Article and Find Full Text PDFThe applications of 2-hydroxy-β-nitrostyrenes as efficient bifunctional intermediates in organic synthesis are investigated in this review. For this purpose, reactions of 2-hydroxy-β-nitrostyrenes with diverse molecules, including carbonyl compounds, 1,3-dicarbonyl compounds, α,β-unsaturated carbonyl compounds, hemiacetals, nitroalkenes, γ-butenolides, tetronic acid, azalactones, pyrazolones, enamines, malononitrile, methyleneindolinones, ylides, , were investigated to construct interesting biologically active scaffolds such as chromans, chromenes, coumarins, benzofurans and their fused and spiro rings, natural products, and other useful cyclic and acyclic compounds. The main focus is on the asymmetric synthesis of these compounds cascade/domino/tandem reactions catalyzed by chiral organocatalysts.
View Article and Find Full Text PDFNitroepoxides were introduced as efficient substrates for the one-pot three-component synthesis of 2-iminothiazoles under catalyst-free conditions. Reaction of amines, isothiocyanates, and nitroepoxides in THF at 10-15 °C afforded corresponding 2-iminothiazoles in high to excellent yields. The reaction proceeds via the in situ formation of thiourea from an amine and an isothiocyanate, followed by nitroepoxide ring opening with the sulfur of thiourea, cyclization reaction, and dehydration cascade.
View Article and Find Full Text PDFA metal-free multicomponent synthetic route for the diverse preparation of dithiocarbamate-containing piperazine derivatives was developed through the C-N bond cleavage of DABCO ring. This multicomponent re-engineering approach proceeds the reaction of amines, CS and DABCO salts in one pot. Various DABCO salts and secondary amines are tolerated well in this protocol to afford a broad spectrum of dithiocarbamate-containing piperazines in good to high yields.
View Article and Find Full Text PDFReaction of glycine-based dithiocarbamates with nitroalkenes in the presence of acetic anhydride was utilized for the synthesis of fully substituted 2-(alkylsulfanyl)-4-(nitroalkyl)-5-acyloxy-1,3-thiazoles. The reaction proceeds the formation of thiazol-5(4)-one from glycine-based dithiocarbamates, followed by the Michael addition of this intermediate to nitroalkenes, aromatization, and esterification reaction cascade. This new one-pot three-component reaction afforded a diverse library of fully substituted thiazoles in high to excellent yields under solvent-free conditions.
View Article and Find Full Text PDFNitroepoxide ring opening with thionucleophiles such as potassium xanthates, sodium aryl sulfinates and sodium bisulfite in water is investigated. It provides a direct and green route for the synthesis of α-xanthyl-α-aryl-2-propanones (P2P-xanthate derivatives), β-keto sulfones and β-keto sulfonic acids. High to excellent yields, performing the reaction in water under catalyst-free conditions, and easy work-up are the main advantages of this protocol.
View Article and Find Full Text PDFThe applications of DABCO (1,4-diazabicyclo[2.2.2]octane) in the synthesis of piperazine derivatives including biologically active compounds C-N bond cleavage are investigated in this review.
View Article and Find Full Text PDFThe synthesis of a novel category of pseudo-peptides via intramolecular Ugi reaction of levulinic acid (4-oxopentanoic acid), aromatic and aliphatic amines, and amino acid-based isocyanides is reported. Levulinic acid was applied as a bifunctional substrate containing both carbonyl and acid moieties suitable for the Ugi reaction. This article provides a facile and convenient one-pot procedure for the synthesis of peptide-like heterocyclic molecules containing 2-pyrrolidone (γ-lactam), amide and ester functional groups with good to excellent yields.
View Article and Find Full Text PDFConsecutive multicomponent reactions have been applied for the synthesis of novel pseudo-peptides bearing dithiocarbamate and N,X-heterocyclic groups (X = S, O) in only one structure. The first multicomponent reaction includes the synthesis of dithiocarbamates using an amine or amino acid, CS and an electrophile. The second MCR is synthesis of Asinger imines using 2-chloroisobutyraldehyde, NaXH (X = S, O), ketone and ammonia.
View Article and Find Full Text PDFA one-pot three-component route for the direct introduction of dithiocarbamates into indoles using a C-H sulfenylation strategy mediated by molecular iodine is disclosed. Various indole derivatives including 1-methylindole, 2-methylindole, 3-methylindole, and 5-substituted indoles were applied successfully in this protocol to afford diverse indole-dithiocarbamates containing the dithiocarbamate group on the position two or three in good to high yields. The reactions do not require transition metals or disulfiram but use an environmentally benign solvent and simple commercially available starting materials.
View Article and Find Full Text PDFNitroepoxides are easily transformed into benzodiazepines, tetrahydrobenzodiazepines, imidazopyridines, and N-alkyl tetrahydroquinoxalines by treatment with 2-aminobenzylamines, 2-aminopyridines, and N-alkyl 1,2-diaminobenzenes, respectively. Regioselectivity is controlled through attack of the most nucleophilic nitrogen of the unsymmetrical diamine to the β position of the epoxide. These reactions represent an efficient way to prepare privileged bioactive structures.
View Article and Find Full Text PDFA one-pot three-component route for the synthesis of -trifluoromethyl dithiocarbamates by the reaction of secondary amines, carbon disulfide and Togni's reagent is described. The reactions proceed in moderate to good yields. A similar reaction using a primary aliphatic amine afforded the corresponding isothiocyanate in high yield.
View Article and Find Full Text PDFA facile and efficient procedure for the synthesis of substituted thiazole-2(3H)-thiones and thiazolidine-2-thiones by the reaction of primary amines, carbon disulfide, and nitroepoxides is described. By using secondary amines in this protocol, the corresponding dithiocarbamate-substituted phenyl-2-propanones were prepared in excellent yields. In addition, substituted thiazoles and 1-(alkylthio)-1-phenylpropan-2-ones were prepared in reactions of S-alkyl dithiocarbamates and nitroepoxides.
View Article and Find Full Text PDFAn efficient one-pot, four-component reaction for the synthesis of dithiocarbamates using carbon disulfide, cyclic imines, acid chlorides, and commercially available primary or secondary amines has been developed by performing an acid chloride addition to a heterocyclic imine followed by subsequent nucleophilic substitution of in situ generated dithiocarbamic acid. With the aid of the newly developed and powerful multicomponent reaction, a direct route for the synthesis of 24 unknown dithiocarbamates in moderate to good yield under mild conditions is enabled.
View Article and Find Full Text PDFAn efficient approach for the synthesis of novel alkyl 2,3-dihydro-3-oxo-1-aryl-1H-benzo[f]chromen-2-ylcarbamodithioates and alkyl 3,4-dihydro-2-oxo-4-aryl-2H-chromen-3-ylcarbamodithioates from 2-(alkylthio)thioazlactones (thioazlactones) and phenols or naphthols catalyzed by PTSA was developed. The reaction proceeds via a domino esterification/intramolecular 1,4-addition-type Friedel-Crafts alkylation reaction to afford interesting complex molecules by a simple procedure with high yields and diastereoselectivity. An X-ray analysis was carried out to firmly establish the stereochemistry of the products.
View Article and Find Full Text PDFA reaction of dithiocarbamic acid salts with carbonyl compounds was investigated for the first time in the presence of BF(3)·OEt(2). The reaction is temperature dependent and gives gem-bis(dithiocarbamates) at 35-45 °C as a molecule with high equivalents of dithiocarbamate groups. At lower temperatures (15-20 °C), the 2-iminium-1,3-dithietane is obtained as the only product.
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