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A novel palladium-catalyzed protocol for the synthesis of 2-arylquinolines via tandem reaction of 2-aminostyryl nitriles with arylboronic acids has been developed with good functional group tolerance. The presented approach offers a new synthetic pathway toward the core structures of 2-arylquinolines compared to classical condensation reaction of (E)-2-aminostyryl aryl ketones. Moreover, the present synthetic route could be readily scaled up to gram quantity without difficulty. Preliminary mechanistic experiments showed that this transformation involves a nucleophilic addition of aryl palladium species to the nitrile to generate an aryl ketone intermediate followed by an intramolecular cyclization and dehydration to quinoline ring.

A palladium-catalyzed cascade reaction of 2′-acetyl-[1,1′-biphenyl]-2-carbonitriles with arylboronic acids is developed. This reaction affords a new class of seven-membered 5-arylidene-7-aryl-5H-di...

A lanthanide-catalyzed intermolecular hydroamination of 2-alkynylbenzonitriles with secondary amines has been disclosed, providing a streamlined access to a range of aminoisoindoles in moderate to excellent yields. The salient features of this reaction include high bond-formation efficiency, mild reaction conditions, 100 % atomic efficiency and good functional group tolerance. This methodology has also been successfully applied to the construction of other nitrogen-containing compounds, such as 5 H-imidazo[2,1-a]isoindoles and isoquinolines. A plausible mechanism for the formation of aminoisoindoles involving initial N-H activation by a lanthanide complex followed by C≡N insertion into a Ln-N bond to form an amidinate lanthanide intermediate, which undergoes the cyclization is proposed.

The synthesis of 2,4-disubstituted quinazolines by a palladium-catalyzed reaction of arylboronic acids with N-(2-cyanoaryl)benzamides has been developed with moderate to excellent yields. The method shows good functional group tolerance. In particular, halogen and hydroxyl substituents, which are amenable for further synthetic elaborations, are well tolerated. Moreover, the present synthetic route could be readily scaled up to gram quantity without difficulty. The mechanism possibly involves nucleophilic addition to the nitrile function, forming an imine intermediate followed by an intramolecular addition to the amide and dehydration to the quinazoline ring.

The first example of the direct halosulfenylation of benzo[b]furans with commercially available disulfides and N-halosuccinimides has been achieved, providing an efficient metal-free synthetic pathway to access diverse 3-halo-2-thiobenzo[b]furans in moderate to excellent yields. In particular, a halogen (e.g., bromo or iodo) substituent on the benzo[b]furan ring is amenable for further synthetic elaborations thereby broadening the diversity of the products.

A palladium-catalyzed cascade reaction of 2'-acetyl-[1,1'-biphenyl]-2-carbonitriles with arylboronic acids is developed. This reaction affords a new class of seven-membered 5-arylidene-7-aryl-5

A palladium-catalyzed tandem reaction of 2-(cyanomethyl)benzonitriles or 2-(2-carbonylphenyl)acetonitriles with arylboronic acids in water has been developed for the first time. This reaction features good functional group tolerance and provides a new strategy for the synthesis of diverse isoquinolines under mild conditions. The use of water as the reaction medium makes the synthesis process environmentally benign. Preliminary mechanistic experiments indicate that the major reaction pathway involves carbopalladation of the C(sp3)–cyano group and subsequent intramolecular cyclization findings that were further supported by density functional theory (DFT) calculations.

The first example of the palladium-catalyzed tandem addition/cyclization of 2-(benzylidenamino)benzonitriles with arylboronic acids has been developed. This transformation features good functional group tolerance and provides an alternative synthetic pathway to access 2,4-diarylquinazolines in moderate to good yields. A plausible mechanism for the formation of 2,4-diarylquinazolines involving sequential nucleophilic addition followed by an intramolecular cyclization is proposed.

The first example of the palladium-catalyzed, three-component tandem reaction of 2-aminobenzonitriles, aldehydes, and arylboronic acids has been developed, providing a new approach for one-pot assembly of diverse quinazolines in moderate to good yields. A noteworthy feature of this method is the tolerance of bromo and iodo groups, which affords versatility for further synthetic manipulations. Preliminary mechanistic experiments indicate that this tandem process involves two possible mechanistic pathways for the formation of quinazolines via catalytic carbopalladation of the cyano group.

An efficient protocol to construct 2-arylindoles was developed through palladium-catalyzed tandem addition/cyclization of potassium aryltrifluoroborates with aliphatic nitriles in aqueous medium. The use of water as the reaction medium makes the synthesis process environmentally benign. A plausible mechanism for the formation of 2-arylindoles involving sequential nucleophilic addition followed by an intramolecular cyclization is proposed. Moreover, the utility of this catalytic tandem transformation was also demonstrated in an efficient gram-scale synthesis. This method provides an alternative synthetic tool for accessing a more diverse array of 2-arylindoles.

The first example of the palladium-catalyzed sequential nucleophilic addition followed by an intramolecular cyclization of functionalized nitriles with arylboronic acids has been achieved, providing an efficient synthetic pathway to access structurally diverse isoquinolines and isoquinolones. This methodology has also been successfully applied to the total synthesis of the topoisomerase I inhibitor CWJ-a-5 (free base).

Rongalite® promotes cleavage of diaryl disulphides generating the corresponding thiolate species in situ which then undergo facile ring-opening of epoxides in a regioselective manner under ultrasound irradiation, affording β-hydroxy sulphides in good to excellent yields. The important features of this methodology are base-free, odourless, high yield, reasonably rapid reaction rate, simple workup, high regioselectivity, cost-effective and no requirement of transition metal catalysts. It is noteworthy that ring-opening reaction of 1,2-diphenyldiselane with 2-(phenoxymethyl)oxirane are also conducted smoothly to afford β-hydroxy selenide in excellent yield under the standard conditions.

Relative carrying capacity of resources is an index to measure sustainable development through carrying capacity. Case studies of eleven cities in Zhejiang (Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou and Lishui) illustrated regional sustainable development approach. In this study, to provide insight into spatial and dynamic analysis of region sustainable development, we calculated the relative carrying capacity of land resources and economical resources and synthetical carrying capacity of resources in different cities in Zhejiang, and geographic information system was carried out. The results showed that all cities but Hangzhou and Ningbo were ecologically sustainable, and relative carrying capacity of land resources in northern and eastern Zhejiang was larger than those in southern and western Zhejiang. The sampling years of Wenzhou, Hangzhou and Ningbo contribution rates of land resource to synthetic carrying capacity were grouped into three stages, and there were two milestones trends and changes in 1996 and 2004, respectively. This study demonstrated that geographic information system and relative carrying capacity of resources are effective for assessment of region sustainable development, and provide policy guidelines for decision-making.

Ultrasound assisted ring-opening of epoxides with 1,2-diphenyldiselenide in PEG-400/H2O in the presence of sodium dithionite has been developed, affording β-hydroxy selenides with high regioselectivity in good to excellent yields. Importantly, the present protocol is very practical and highly efficient since it does not require the use of expensive and unpleasant smelly reagent.

An efficient and simple method for the regioselective synthesis of β-hydroxy sulfides via Rongalite-promoted reaction of epoxides with diaryl disulfides under ultrasound irradiation is developed.

The title reaction provides a practical and efficient method for the regioselective synthesis of β-hydroxy selenides.

The title reaction tolerates a diversity of functional groups like ether, nitro groups and aromatic halides.

An efficient and convenient condensation reaction of 2-aminothiophenol with aldehydes catalyzed by a catalytic amount of ceric ammonium nitrate in polyethylene glycol was investigated. As a result, a set of diverse 2-substituted benzothiazoles such as 2-phenylbenzothiazole as well as its p-Me, p-NO2, p-F, p-Cl, p-Br, o-OMe, p-OMe and 2-furyl, 2-pyridyl and styryl derivatives were obtained in good to excellent yields for 5 h at room temperature. Additionally, the catalyst system was recovered and reused several times without evident loss in activity. Copyright © 2011 John Wiley & Sons, Ltd.