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Sulfur-containing organophosphorus molecules have played a pivotal role in organic chemistry, thereby motivating researchers worldwide to establish S–P bonds from more environmentally friendly phosphorus sources.

A halotrimethylsilane (TMSX) accelerated cascade halophosphorylation and cycloisomerization of γ-hydroxyl ynones with diphenylphosphine oxides is presented. This methodology allows the one-step synthesis of practical polysubstituted halophosphorylated dihydrofuran derivatives. It is noteworthy that halotrimethylsilane functions as a halogenation reagent as well as a promoter to initiate this transformation. In addition, the reaction system can also be scaled up to gram quantities, and the produced halogenated compounds can undergo further derivatizations by Pd-catalyzed coupling reactions.

With the development of ortho C-H functionalization in Pd/NBE chemistry, the catalytic systems used are becoming increasingly complex. The increasingly complex catalytic systems may have created technical barri-ers for researchers in other fields to apply Pd/NBE chemical methods. This report describes the use of a simple Pd/NBE catalytic system to achieve ortho C-H oxylation and phosphonylation and other functionalization of iodobenzene through templated conversion reactions. The key point of this method is to explore the previous-ly unknown step of introducing dimethylamine in the ortho position of iodobenzene through C-H amination. Aryl dimethylamine is quickly converted to methyl quaternary ammonium salt precipitation, and methyl qua-ternary ammonium salt effectively avoids Hofmann elimination in the subsequent functionalization.

Herein, a facile and environmentally friendly oxidative coupling reaction to obtain unsymmetrical disulfide compounds, without using metal or organic dyes as photocatalyst and only using a catalytic amount of iodine, was developed. Oxygen is used as oxidant in the reaction and the substrate scope is wide. A gram-scale synthesis also highlights the synthetic practicality of this photochemical strategy. Moreover, our mechanistic studies support the formation of disulfide products through free-radical coupling.

The report describes a visible light promoted carbochloromethylation of 2-bromomethyl acrylate and N-arylmethacrylamide, and a series of trihalomethyl substituted allylic acid esters and indolone derivatives were synthesized.

N-doped porous carbon (NC) was synthesized from sugar cane bagasse, which is a sustainable and widely available biomass waste.

Visible-light-promoted cyclization and aromatization of chalcones with 2-mercaptobenzimidazoles have been successfully developed to obtain diverse imidazo[2,1

The free radical cyclization reaction is a promising strategy for ring framework formation. Herein, we report a copper-catalyzed tandem radical cyclization strategy for preparing substituted lactam derivatives. This reaction proceeds through a radical coupling approach, which not only allows a wide range of alkenes but also is quite compatible with the primary, secondary, and tertiary radicals. In addition, density functional theory calculations were performed to gain insights into the reaction mechanism.

A method for the electrochemical synthesis of sulfinic esters by aerobic oxidative coupling of thiophenols and alcohols has been developed. Using electrons as the redox reagent and O2 in air as the oxygen source, the reactions proceeded smoothly at room temperature, even for a gram-scale preparation. No use of catalyst, clean redox reagent, green and abundant oxygen source, and mild reaction conditions make this strategy eco-friendly.

The inverse vulcanization (IV) of elemental sulfur to generate sulfur-rich functional polymers has attracted much recent attention. However, the harsh reaction conditions required, even with metal catalysts, constrains the range of feasible crosslinkers. We report here a photoinduced IV that enables reaction at ambient temperatures, greatly broadening the scope for both substrates and products. These conditions enable volatile and gaseous alkenes and alkynes to be used in IV, leading to sustainable alternatives for environmentally harmful plastics that were hitherto inaccessible. Density functional theory calculations reveal different energy barriers for thermal, catalytic and photoinduced IV processes. This protocol circumvents the long curing times that are common in IV, generates no H

A Cu-catalyzed stereospecific denitro silylation of β-nitroalkenes with silanes for the synthesis of vinylsilanes using DTBP as the oxidant was developed. This method presented an inexpensive and non-toxic catalytic system with an appropriate substrate scope. This approach is (E)-specific and produced an important class of vinylsilanes in good yields.

An efficient palladium-catalyzed Hiyama reaction between various pyrimidin-2-yl tosylates with organosilanes has been developed. The use of CuCl with TBAF as additive is essential for promotion of the construction of the carbon–carbon bond. This procedure shows wide functional group tolerance for electrophilic pyrimidin-2-yl tosylates and has been extended to aromatic amino-substituted pyrimidin-2-yl tosylates, affording the desired C2-aryl and alkenyl pyrimidine derivatives in good to excellent yields.

Glycerol is a new green organic solvent. It not only acts as a phase transfer catalyst but also as a recyclable solvent by significantly enhancing the intramolecular cyclization. A series of 4-aryl-7,7 -dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin derivatives were synthesized by one-pot multicomponent reaction of Meldrum’s acid with benzaldehyde, and cyclohexanedione in glycerol. Compared to classic methods, this method has the advantages of milder reaction conditions, good yields, easy processing and environmental benignity.

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Metal-organic frameworks (MOFs) are coordination polymers with potential voids constructed by organic ligands and metal ions. In this work, we employed a semi-rigid polycarboxylic acid ligand 5-(4-carboxyphenoxy)methyl)benzene-1-thio-3-dicarboxylic acid (H3L) with the flexible “–CH2-O-” group between the two phenyl groups to construct a new Cu(II)-MOF {[Cu2L(OH)]·DMF}n (1). The structure analysis reveals that the adjacent Cu(II) cations are bridged by oxygens from OH– anion and carboxy group to get a one dimensional infinite rod-shaped secondary building unit (SBU). Furthermore, compound 1 exhibits an intriguing three-dimensional MOF based on infinite rod-shaped SBUs and L3-. PXRD result shows compound 1 is still stable after placed in air for three months. The variable-temperature magnetic studies indicate antiferromagnetic behaviors of 1.

Here we show that the base-catalyzed thio-lactamization of 2-(1-arylvinyl)anilines with CS

We report a general protocol for the direct N-allylation of electron-poor N-heterocyclic amides and sulfonamides via an amide-aldehyde-alkene condensation reaction catalyzed by a Lewis acid. This process has a broad substrate scope with respect to N-heterocyclic amides including carbamates, carboxamides, and N-methylsulfonamides, and provides efficient access to a variety of allylamine derivatives in good yield with high regioselectivity. The utility of this method was also demonstrated by the rapid synthesis of Naftifine from N-methyl-1-naphthamide, paraformaldehyde, and styrene in one-pot.

New 2-(1,2,3-triazol-1-yl)pyrimidines were synthesized in good yields by the three-component reaction of pyrimidin-2-yl sulfonates, sodium azide and active methylene ketones in the presence of K2CO3 at room temperature. This procedure eliminates the need to handle organic azides in the synthesis of analogous compounds.

A rapid and efficient method for the preparation of new pyrido[2,3-d]pyrimidinone derivatives by the condensation of 2-amino-4-aryl-6-arylnicotinamides with carbon disulfide or cycloalkanones under focused microwave irradiation is described.

The straightforward visible-light-induced synthesis of stilbene compounds via the cross-coupling of nitroalkenes and diazonium tetrafluoroborates under transition-metal-free conditions is described. The protocol uses green LEDs as light sources and eosin Y as an organophotoredox catalyst. Broad substrate scope and exclusive selectivity for the (E)-configuration of stilbenes are observed. This protocol proceeds via a radical pathway, with nitroalkenes serving as the radical acceptor, and the nitro group is cleaved during the process.

A series of 1-aryl-1,2-dihydrobenzo[f]quinolin-3(4H)-one derivatives and 4-aryl-7,7-dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin derivatives have been synthesized by one-pot multicomponent reaction of Meldrum’s acid with benzaldehyde, naphthalene-2-amine, or cyclohexanedione in PEG-400. The method has the advantages of mild reaction conditions, good yields, and easy processing, and is environmentally benign.

Novel thiazolo[2,3-b]quinazolines were prepared by the cyclization reaction between octahydroquinazoline-2-thiones with α-bromoketones, which provides a readily accessible multifunctionalized quinazoline template for diversity-oriented synthesis.

The aza-Michael addition reaction of 4-aryl-7,7-dimethyl-1,2,3,4,5,6,7,8-octahydroquinazoline-2-one/thione-5-ones to α,β-ethylenic compounds in the presence of KF/Al2O3 furnishes N3-substituted quinazolinone derivatives. Those groups (NO2, MeO) with larger steric hindrance at the o-position of the phenyl ring of quinazolinone have an apparent affect on the chemical selectivity thus giving the N1-subsituted products.

The allylation reaction proceeds with high regioselectivity and has a broad substrate scope.

Using rare earth nitrates, tryptophan (L), and sodium citrate (NaL′), three new rare earth ternary complexes (Nd-L-L′· 4H2O, Eu-L-L′ · 4H2O, and La-L-L′ · 4H2O) were prepared. The complexes were characterized by IR, molar conductivity, TG-DTA (thermo gravimetric-differential thermal analysis), 1H NMR, and elemental analyses. TG and elemental analyses of the prepared complexes showed good agreement with their stoichiometry. Compared with two individual ligands, IR spectra of synthesized complexes showed dramatic shift and intensity changes; 1H NMR also showed a slight downfield shift. All analytical results of complexes proved constant composition of M-L-L′ · 4H2O (M = rare earth metal, namely Nd, Eu, or La). Animal tests were also performed to study the anti-coagulation time of these complexes considering also the different concentration of complex Nd-L-L′ · 4H2O. PC-12 pheochromocytoma cells were used to study cell adhesion. Compared with ions of rare earth compounds, rare earth ternary complexes have lower cell toxicity, better cell adhesion, and better anticoagulant action.

The title reactions afford regioselectivity N3- or N1-alkylated quinazolinone derivatives (III) or (V), resp., depending on the steric bulk of the aryl groups.

A simple and highly selective colorimetric sensor (L1) bearing thiosemicarbazide moiety as binding site and nitrophenyl moiety as signal group were synthesized. Sensor L1 showed great colorimetric single selectivity and high sensitivity for mercury cation in DMSO and DMSO/H(2)O binary solutions. When Hg(2+) was added to the DMSO solution of L1, dramatic color change from brown to colorless was observed. While the cations Ca(2+), Mg(2+), Cd(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Pb(2+), Ag(+) and Cr(3+) could not cause any distinct interferer toward the recognition process for Hg(2+). The detection limit is allowable to 5.0 × 10(-6) and 1.0 × 10(-7)M level of Hg(2+) according to visual color change and UV-vis change, respectively. The recognition mechanism of the sensor toward mercury cation was evaluated in DMSO solutions by UV-vis and (1)H NMR. The sensor selectively sense Hg(2+)via the formation of a stable 1:1 complex through CS and CO group with Hg(2+). When these complex bonds formed, the sensor carried out an ICT transition induced color change.