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Neue konjunktive β-silylierte organometallische Li-, Mg- und Zn-Reagentien wurden hergestellt und fur den Aufbau einer Vielzahl von polyfunktionalisierten 5-, 6- und 7-gliedrigen Heterocyclen wie Furane, Pyrrole, Chinoline, Benzo[b]thieno[2,3-b]pyridin, Naphthyridine, kondensierte Pyrazole und 2,3-Dihydrobenzo[c]azepine verwendet. Die endstandige Silylgruppe konnte in den meisten Heterocyclenklassen in neue Kohlenstoff-Kohlenstoff-Bindungen umgewandelt werden.

The large diatom Coscinodiscus asteromphalus was separated from seawater in Jiaozhou Bay using a repeated precipitation method and then its chemical compositions of carbon (C), nitrogen (N), phosphorus (P), and silicon (Si) combined with chlorophyll a (Chl a) were examined for the first time for a natural population in this study. Results show that the contents of carbon, nitrogen, phosphorus, silicon, and Chl a in C. asteromphalus cells were 35,610.5, 9374.2, 352.4, 1105.5, and 1767.0 pg/cell, respectively, and the corresponding molar ratios of C/N, N/P, Si/P, and Si/N in C. asteromphalus cells were 4.5, 66.0, 2.7, and 0.07, respectively, which are different from the Redfield ratio. Additionally, their C/Chl a mass ratio was 23.2. High N/P ratio and low Si/P and Si/N ratios in C. asteromphalus cells were consistent with those in particulates of any size and seawater in the bay, reflecting an ecological response of phytoplankton to the nutrient structure of seawater, suggesting Si limitation to phytoplankton growth. The fact that C. asteromphalus spread all over the bay mainly in summer and autumn and the fact that Chl a content in C. asteromphalus cells could account for a maximum percentage of 78% of those in the water column suggest that the contribution of C. asteromphalus to phytoplankton biomass was significant in Jiaozhou Bay.

New conjunctive β-silylated organometallic reagents of Li, Mg, and Zn have been prepared and used for an expeditive construction of various polyfunctionalized 5-, 6-, and 7-membered heterocycles, such as furans, pyrroles, quinolines, benzo[b]thieno-[2,3-b]pyridine, naphthyridines, fused pyrazoles, and 2,3-dihydro-benzo[c]azepines. The latent silyl group has been converted into various carbon–carbon bonds in most heterocycle types.

Based on field investigations in the Changjiang River mouth, rain sampling from the river's upper reaches to the mouth, historical data, and relevant literatures, the budget and major control factors of total phosphorus (TP) and dissolved inorganic phosphorus (DIP) in the river catchment were estimated and discussed from the catchment scale. It will supply a base for effective controlling P concentration in the Changjiang River and its mouth. Results show that the export fluxes of TP and DIP were mainly controlled by the river runoff. The TP and DIP in the Changjiang River came mainly from agricultural nonpoint source P losses from fertilizer and soil and point sources of industrial waste and residential sewage discharges. The export fluxes of TP and DIP in the river mouth were only 27.0% and 28.3% of the imports from the river catchment, respectively, suggesting that most of P were removed in transportation. A mass of freshwater marshes in the river catchment were the main areas to remove P. Significant increasing in utilization of fertilizer P and incessant increasing in water and soil loss areas were the primary reasons of agricultural nonpoint source P losses. How to decrease the agricultural nonpoint source P loss from the catchment scale is a key controlling P concentration in the Changjiang River and its mouth. The point source industrial waste P discharge has been primarily treated in the river catchment, but the residential sewage P discharge needs further control.

Alkyl indium compounds are prepared through a CuCl-mediated direct insertion of indium into alkyl iodides or bromides under an air atmosphere and even in the presence of water.

We report an efficient method for the preparation of aryllithium and zinc reagents from inexpensive and readily available aryl chlorides by using lithium 4,4′-di-tert-butylbiphenylide (LiDBB) as a lithiation reagent. The resulting organometallic reagents underwent subsequent reactions with a variety of electrophiles, such as an aldehydes, DMF, PhSSO2Ph, TsCN, an aryl halide, or an acid chloride (through Pd-catalyzed cross-coupling). Aryl chlorides bearing substituents, including methoxy, 3,4-methylenedioxy, fluoride, TMS, OTMS, NMe2, acetal, and ketal, were shown to be appropriate substrates. Interestingly, aryl chlorides containing a formyl group could also be used, provided that the formyl group was temporarily converted into an α-amino alkoxide by using the lithium amide of N,N,N′-trimethylethylenediamine (LiTMDA). The presence of a hydroxyl group was also tolerated when it was deprotonated with n-BuLi prior to the addition of LiDBB.

The stereoselective synthesis of cyclic and acyclic (E)- or (Z)-alkenylindium halides is described.

A convenient, efficient, and practical method for the synthesis of β-indolylketones via a condensation of indole, aromatic aldehydes, and deoxybenzoin under ultrasonic irradiation was described. It provided a novel base-promoted approach for the one-pot synthesis of β-indolylketones.

A facile Michael addition of ferrocenylenones with aliphatic amines under ultrasound irradiation in the absence of solvent and catalyst at room temperature can afford 1-ferrocenyl-3-amino carbonyl compounds rapidly in high yields, which is also efficient in the aza-Michael reaction of other α,β-unsaturated carbonyl compounds such as chalcone, carboxylic ester, etc. However, aromatic amines do not undergo the conjugate addition at all, and the reactions under existing methods do not proceed or take place in low yield after a long reaction time. Apart from experimental simplicity, generality and selectivity, the advantages of this methodology are the rapid, environmentally benign and less expensive processes, which will contribute to the progress of green chemistry.

Starting from aryl, heteroaryl, alkyl bromides, and benzyl chlorides the corresponding triorganyl indium derivatives are prepared in one step followed by the Pd-catalyzed cross-coupling reaction leading to a wide range of biaryls, biarylmethanes and alkylated aryl products.

The simple protocol renders possible the highly diastereoselective synthesis of various title structures via InBr3-catalyzed Prins-polyene cyclization with aldehydes, acetals, and ketones.

Diels—Alder reactions involving both alkyl- and aryl-substituted α,β-unsaturated aldehydes (I) and cyclopentadiene (II) proceed efficiently in the presence of the title catalyst and trifluoroacetic acid as the acidic co-catalyst.

The synthesis of recyclable ionic liquid-supported imidazolidinone catalyst I and its application in 1,3-dipolar cycloaddition of nitrone with α,β-unsaturated aldehyde with high performance were described. Most importantly, the catalyst I can be recovered and recycled for up to five runs without observing significant decrease in catalytic activity.

Cascades: An InBr(3)-catalyzed intermolecular polyene cyclization initiated by a Prins reaction provides a concise approach to 3-oxaterpenoid derivatives. The reaction is compatible with various aldehydes, ketones, and polyolefin-alcohol substrates. In addition, the total synthesis of (±)-moluccanic acid methyl ester was achieved in seven steps by using such a Prins-polyene cyclization as the key step.

The synthesis of a variety of title furoindole derivatives, e.g. (V) and (VIII), is presented, involving a three-component coupling of 1,3-diketones with o-halobenzaldehydes and isocyanides, followed by intramolecular Cu-catalyzed Ullmann reaction.

The synthesis of ester-containing indium homoenolates via a direct insertion of indium into ω-halo esters (I) or -ketones (IV) in the presence of CuI/LiCl is described.

The microwave-assisted Michael addition of diethyl malonate (II) to ferrocenyl-substituted chalcones (I) under solvent-free conditions is described.

Alkyl indium compounds are prepared through a CuCl-mediated direct insertion of indium into alkyl iodides or bromides under an air atmosphere and even in the presence of water.

An efficient palladium-catalyzed cross-coupling of indium homoenolate with aryl halide is described. The reactions proceeded efficiently in DMA at 100 °C to afford the desired products of β-aryl ketones in moderate to good yields. Various important functional groups including COR, COOR, CHO, CN, OH, and NO(2) can be well tolerated in the protocol.

The synthetic utility of the indium homoenolates (II) is demonstrated by the synthesis of 1,4-dicarbonyl compounds which are not readily available by conventional methods.

Both reactions of 1,5-keto—olefin substrates are achieved with exclusive diastereoselectivity and high enantioselectivity by tuning the substrates or forcing the reaction conditions.

An efficient method for the synthesis of a series of ferrocenylcyclohexenones via tandem Michael–aldol reaction of ferrocenyl-substituted chalcones with dibenzyl ketone under solvent-free conditions is described. It was found that the factors including the electronic nature of chalcone, basicity of the base, reaction time, and temperature have effects on the formation of the ferrocenylcyclohexenones.

A zinc/indium chloride−mediated pinacol cross-coupling reaction between aldehyde and α,β-unsaturated ketone in aqueous media was developed. The 1,2-diols were obtained in moderate to good yields with up to 93:7 diastereoselectivity.

Ionic liquid [bmim]BF4 has been demonstrated to be an efficient and environmentally friendly reaction medium as well as reaction promoter for the synthesis of O-acetyl cyanohydrin via one-pot condensation of aldehyde, TMSCN, and Ac2O without Lewis acid or any special activation. In addition, the recovered ionic liquid could be reused for subsequent runs without the loss of activity.

The alkali salt of L-proline was demonstrated to be an efficient and practical catalyst for the cyanosilylation of a wide variety of simple and functionalized carbonyl compounds under solvent-free conditions. The reactions proceeded smoothly at room temperature to afford the corresponding cyanohydrins in good to excellent yields.

An efficient method for the Barbier-type alkylation reaction of various nitrones (including chiral version) and alkyl halides in water is described. The amines and hydroxylamines can be obtained in good yields, depending on the judicious choice of the metal complexes used.

An efficient method for the conjugate addition of unactivated alkyl iodides to α,β-unsaturated carbonyl compounds using indium/copper in water is described. The reactions proceed more efficiently in water than in organic solvents. In, CuI, and InCl3 are all essential for efficient reaction. Formation of a symmetrical vic-diarylalkane is observed when an aryl-substituted alkene is used as substrate.

A mild, efficient and environmentally friendly method has been developed for the synthesis of α-aminonitriles via a three-component condensation of aldehyde, amine and TMSCN in the presence of a catalytic amount of indium(III) iodide in water. The reactions proceeded smoothly at room temperature in water to generate the corresponding products in moderate to excellent yields.

An efficient method has been developed for the Barbier–Grignard-type alkylation reaction of aldehydes (including aliphatic version) using unactivated alkyl halides in water in the presence of an In/CuI/I2 or In/AgI/I2 system. The reactions proceeded more efficiently in water than in organic solvent. In, CuI or AgI, and I2 were all essential for the efficient progress of the reactions. A radical-type reaction mechanism was studied and proposed by using 4-pentenal as substrate.

A practical and efficient method for the synthesis of optically active O-acetyl cyanohydrins via one-pot lipase-catalyzed kinetic resolution of the in situ generated racemic cyanohydrins or O-acetyl cyanohydrins using an ionic liquid as both reaction media and promoter has been described.

In the presence of In or Zn/AgI/InCl(3), an efficient and practical method for the Barbier-Grignard-type alkylation reactions of simple imines by using a one-pot condensation of various aldehydes, amines (including the aliphatic and chiral version), and secondary alkyl iodides has been developed. The reaction proceeded more efficiently in water than in organic solvents. Without the use of CuI, it mainly gave the imine self-reductive coupling product, which was not the alkylated product. Good diastereoselectivities (up to 92:8 dr) were obtained when L-valine methyl ester was used as the substrate.

An efficient system of In/CuI/InCl3 was developed for Barbier−Grignard-type alkylation reactions of simple imines, using a one-pot condensation of various aldehydes, amines (including aliphatic and chiral version), and alkyl iodides in water or aqueous media. The reactions proceeded efficiently at room temperature to give the desired products in moderate to good yields. Good diastereoselectivities were obtained when using l-valine methyl ester as substrate.

N, P and SiO3-Si in the Changjiang mainstream and its major tributaries and lakes were investigated in the dry season from November to December, 1997, and in the flood season in August and October, 1998. An even distribution of SiO3-Si was found along the Changjiang River. However, the concentrations of total nitrogen, total dissolved nitrogen, dissolved inorganic nitrogen, nitrate and total phosphorus, total particulate phosphorus increased notably in the upper reaches, which reflected an increasing impact from human activities. Those concentrations in the middle and lower reaches of the Changjiang River were relatively constant. Dissolved N was the major form of N and the particulate P was the major form of P in the Changjiang River. The molar ratio of dissolved N to dissolved P was extremely high (192.5-317.5), while that of the particulate form was low (5.6-37.7). High N/P ratio reflected a significant input of anthropogenic N such as N from precipitation and N lost from water and soil etc. Dissolved N and P was in a quasi-equilibrium state in the process from precipitate to the river. In the turbid river water, light limitation, rather than P limitation, seemed more likely to be a controlling factor for the growth of phytoplankton. A positive linear correlationship between the concentration of dissolved N and the river's runoff was found, mainly in the upper reaches, which was related to the non-point sources of N. Over the past decades, N concentration has greatly increased, but the change of P concentration was not as significant as N. The nutrient fluxes of the Changjiang mainstream and tributaries were estimated, and the result showed that the nutrient fluxes were mainly controlled by the runoff, of which more than a half came from the tributaries. These investigations carried out before water storage of the Three Gorges Dam will supply a scientific base for studying the influences of the Three Gorges Dam on the ecology and environment of the Changjiang River and its estuary.

This article describes a fast, efficient, economical, and environmentally friendly method for the preparation of a series of ferrocenyl‐substituted 1,5‐diketone compounds via Michael addition of ferrocenyl‐substituted chalcones with deoxybenzoin or dibenzyl ketone under solvent‐free conditions, and affords the corresponding Michael adducts with excellent yields of 77–93%.

Ionic liquid [omim][PF6] has been demonstrated as an efficient and environmentally friendly reaction media as well as a promoter for the cyanosilylation of aldehydes under mild conditions. In addition, the recovered ionic liquid could be reused for subsequent runs with only a gradual decrease in activity.

Mukaiyama aldol and Mukaiyama–Michael reactions can proceed smoothly in the presence of a catalytic amount of DBU (20% mmol), to afford the corresponding products in moderate to good yields. This solvent- and metal-free approach provides an environmentally friendly procedure for Mukaiyama reactions.