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Because of the complex structure and inherent inert chemical activity of lignin, it is still challenging to depolymerize lignin to obtain valuable chemicals efficiently. Here, we present an FeCl 3 -promoted photocatalytic depolymerization strategy to realize the C α -C β oxidative cleavage of lignin model compounds at room temperature. The method generates benzoic acid and phenol compounds in high yields. In addition, the method is effective for the depolymerization of organosolv lignin by cleavage of the products of C α -C β bonds and affords the corresponding products. This strategy provides a method of using an economical photocatalyst to depolymerize lignin and provides a reference for the industrial depolymerization of lignin.

The application of the DMSO/SOCl 2 system enabled the intramolecular cyclization/chlorination of N,N-disubstituted 2-alkynylanilines, leading to the synthesis of a series of 3-chloroindoles with moderate to good yields. Differing from the previously reported interrupted Pummerer reaction featuring the introduction of SMe moiety, the current approach adopted an alternative pathway that realized the incorporation of chlorine atom to the indole skeleton via a desulfonylative chlorocyclization process.

An exclusive thiophene-fused polycyclic π-conjugated 2-arylbenzo[4,5]thieno[2,3- d ]thiazole skeleton was constructed via a one-pot CuCl-mediated three-component reaction, using 2-(2-bromophenyl)acetonitrile and aromatic aldehydes as substrates and elemental sulfur as sulfur source in the presence of K 2 CO 3 and 1,10-phen in DMSO. A plausible reaction mechanism was proposed, which involved formation of benzo[ b ]thiophen-2-amines through cyclization of 2-bromophenyl acetonitrile and sulfur, and subsequent intramolecular condensation/dehydrogenation with aromatic aldehydes.

Highly diastereoselective intramolecular trapping of ammonium ylides with enones has been developed through a Rh(II)/Brønsted acid cocatalytic strategy. This process allows rapid and efficient construction of N-unprotected polyfunctional 2,2,3-trisubstituted indolines in moderate to good yields with excellent diastereoselectivity.

Safety of water was for a long time and still is one of the most pressing needs for many countries and different communities. Despite the fact that there are potentially many methods to evaluate water safety, finding a simple, rapid, versatile, and inexpensive method for detection of toxins in everyday items is still a great challenge. In this study, we extend the concept of composites, impregnated porous fibrous materials, such as fabrics and papers, by single-walled carbon nanotubes (SWNTs), toward very simple but high-performance biosensors. They utilize the strong dependence of electrical conductivity through nanotubes percolation network on the width of nanotube-nanotube tunneling gap and can potentially satisfy all the requirements outlined above for the routine toxin monitoring. An antibody to the microcystin-LR (MC-LR), one of the common culprits in mass poisonings, was dispersed together with SWNTs. This dispersion was used to dip-coat the paper rendering it conductive. The change in conductivity of the paper was used to sense the MC-LR in the water rapidly and accurately. The method has the linear detection range up to 10 nmol/L and nonlinear detection up to 40 nmol/L. The limit of detection was found to be 0.6 nmol/L (0.6 ng/mL), which satisfies the strictest World Health Organization standard for MC-LR content in drinking water (1 ng/mL) and is comparable to the detection limit of the traditional ELISA method of MC-LR detection, while drastically reducing the time of analysis by more than an order of magnitude, which is one of the major hurdles in practical applications. Similar technology of sensor preparation can also be used for a variety of other rapid environmental sensors.