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A catalytic asymmetric N-nitroso aldol reaction of alkenyl trifluoroacetates with nitrosoarenes was achieved using a DTBM-SEGPHOS·AgOTf complex as the chiral precatalyst and KHMDS as the base precatalyst in the presence of methanol. Optically active α-hydroxyamino ketones with up to 89% ee were regioselectively obtained in moderate to high yields not only from acyclic alkenyl esters but also from cyclic ones through the in situ generated chiral silver enolates.

A catalytic enantioselective α-cyanation reaction of β-ketoesters with p-toluenesulfonyl cyanide (TsCN) as a cyanating reagent was achieved using an (R)-BINOL-derived chiral tin dibromide possessing 4-t-butylphenyl groups at the 3- and 3’-positions as the chiral precatalyst in the presence of sodium ethoxide in ethanol. Optically active α-cyano-β-ketoesters having a chiral quaternary carbon were obtained in good to high yields under the influence of the in situ generated chiral tin diethoxide.

A catalytic enantioselective aldol reaction of alkenyl esters with α-keto esters was achieved by using an (R)-BINOL-derived chiral tin dibromide possessing 4-t-butylphenyl groups at the 3- and 3′-positions as a chiral precatalyst in the presence of sodium methoxide and methanol. Optically active aldol products possessing a chiral tertiary carbon were diastereoselectively obtained with up to 92% ee and moderate to high yields, not only from cyclic alkenyl esters, but also from acyclic ones under the influence of the chiral tin methoxide generated in situ.

A catalytic enantioselective aldol reaction of alkenyl esters with isatins was achieved using a DM-BINAP·AgOTf complex as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of methanol or 2,2,2-trifluoroethanol. Optically active 3-alkylated 3-hydroxy-2-oxindoles having up to 98% ee were diastereoselectively obtained in moderate to high yields not only from cyclic alkenyl esters but also from acyclic ones through the in situ generated chiral silver enolates.

The Barbier-type propargylation of azo compounds with α,γ-disubstituted propargylic tosylates was achieved by using metallic barium as the promoter. Various propargylated hydrazines (α-adducts) were exclusively synthesized from the corresponding propargylic tosylates and azobenzenes (diaryldiazenes). The thus-obtained propargylic hydrazines were further efficiently converted into propargylic amines by reductive N–N bond cleavage. Benzidine rearrangement of the propargylic hydrazines was also attempted.

A catalytic, asymmetric allylation reaction of aldehydes or ketones with allyltrimethoxysilane was achieved by using a BINAP·AgBF4 [BINAP = 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl] complex as the chiral precatalyst and triethylamine as the base precatalyst in the presence of 2,2,2-trifluoroethanol. Optically active homoallylic alcohols with up to 95 % ee were obtained in moderate to high yields through the in situ generated chiral allyl silver catalyst.

A catalytic asymmetric O-nitroso aldol reaction of alkenyl trifluoroacetates with nitrosoarenes was achieved by using QuinoxP*·AgOAc [(R,R)-QuinoxP* = (–)-(R,R)-2,3-bis(tert-butylmethylphosphino)quinoxaline] as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of methanol. Optically active α-aminooxy ketones with up to 99 % ee were regioselectively obtained in moderate to high yields by the in situ generated chiral silver enolates.

The Barbier-type allylation of isatin imines with allylic chlorides was achieved by using metallic barium as the promoter. Various α-allylated 3-amino-2-oxindoles were synthesized from the corresponding allylic chlorides and isatin imines. The double-bond geometry of allylic chlorides was retained throughout the reaction. An arylic bromide or iodide functionality of the products was robust to metalation under the optimum reaction conditions.

A catalytic enantioselective Mannich-type reaction of a cyclohexanone-derived alkenyl trichloroacetate with isatin imines was achieved using an (S)-BINOL-derived chiral tin dibromide possessing a 4-tert-butylphenyl group at 3- and 3′-positions as the chiral precatalyst in the presence of sodium methoxide, sodium iodide, and methanol. Optically active 3-alkylated 3-amino-2-oxindoles having up to 90% enantiomeric excess were diastereoselectively obtained in high yields under the influence of the in situ generated chiral tin iodide methoxide.

A couple of planar-chiral ferrocene-fused 4-pyridone derivatives 2a and 2b were synthesized in enantiomerically pure form by scalable asymmetric transformations. Pyridones 2 are versatile precursors to various ferrocene-fused pyridine derivatives, which are useful nucleophilic asymmetric organocatalysts.

The Barbier-type benzylation of azo compounds with benzylic chlorides was achieved by using reactive barium as the promoter. Various benzylic hydrazines were synthesized from the corresponding benzylic chlorides. The thus-obtained benzylic hydrazines were further efficiently converted into benzylic amines by reductive N–N bond cleavage.

A diverse series of chiral bicyclic NHC/Ir complexes were prepared via a previously developed divergent synthesis of chiral imidazolium salts. Among the complexes, 8dz was found to be an excellent catalyst precursor for the Ir-catalyzed asymmetric transfer hydrogenation of ketones. The reaction of ketones with 8dz proceeded smoothly to give corresponding alcohols with high enantioselectivities (up to 98%) and productivities (TON up to 4500).

The enantio- and diastereoselective cross-annulation of cinnamaldehyde (6) and 2,2,2-trifluoroacetophenone (7) was examined to evaluate the performance of newly developed chiral bicyclic imidazoliu...

The industry sector accounts for more than a third of global final energy consumption and nearly the same share of global energy-related CO2 emissions. Compared with other sectors, however, industrial energy modelling has received less attention due to the variety of sub-sectors, impact of energy-saving measures on product qualities and statistical problems. This paper explains how the industry sector is modelled in the World Energy Outlook and presents energy-saving opportunities from energy efficiency in the sector. Using the World Energy Model, a partial equilibrium model, it is found that exploiting the economic potential of energy efficiency can reduce energy demand growth in industry from 1.5 to 1.1 % per year on average over the period 2010–2035. Savings arise from faster adoption of more efficient technologies, phasing out older facilities, process change and system optimisation, including electric motor-driven systems. Significant barriers to the implementation of energy efficiency are the requirement for short payback periods and concerns that change could interrupt production or affect reliability. In order to realise the potential energy savings, policy makers need to address these issues by improving mechanisms for capacity building, energy management and financing.

A catalytic asymmetric aldol reaction of alkenyl trihaloacetates or a γ,δ-unsaturated δ-lactone with aldehydes or an α-keto ester was achieved by using a 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl·silver trifluoromethanesulfonate complex as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of methanol. Optically active α-alkyl β-hydroxy ketones with enantioselectivities of up to 95 % ee were diastereoselectively obtained in moderate to high yields through the in situ generated chiral silver enolates.

The Barbier-type allylation of isatin imines with allylic chlorides was achieved by using metallic barium as the promoter. Various α-allylated 3-amino-2-oxindoles were synthesized from the corresponding allylic chlorides and isatin imines. The double-bond geometry of allylic chlorides was retained throughout the reaction. An arylic bromide or iodide functionality of the products was robust to metalation under the optimum reaction conditions.

A catalytic asymmetric Mannich-type reaction of alkenyl trichloroacetates with aldimines was achieved using SEGPHOS·AgOTf as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of 2,2,2-trifluoroethanol. Optically active β-amino ketones with up to >99% ee were syn-selectively obtained in moderate to high yields via the in situ generated chiral silver enolates.

Go catalytic! A catalytic enantioselective protonation of alkenyl trifluoroacetates was achieved by using an in situ generated chiral tin bromide methoxide as the chiral catalyst in the presence of methanol. Optically active ketones containing a tertiary stereogenic center at the α-position were obtained with enantioselectivities of up to 94 % ee.

The addition of allylic barium reagents to azo compounds was achieved with high α-regioselectivity. The double-bond geometry of allylic barium reagents was retained throughout the reaction at –78 °C and E- or Z-enriched allylic hydrazines were selectively obtained from the corresponding allylic barium reagents. An allylic hydrazine was efficiently converted into an allylic amine by reductive N–N bond cleavage.

The selective synthesis of substituted 4-vinylindoles by the ring-closing enyne metathesis (RCEM)/dehydration sequence is reported. In contrast with many known methods in which a pyrrole ring is constructed onto a functionalized benzene precursor, this method enables the construction of a benzene ring onto a pyrrole precursor. The RCEM/tautomerization sequence for the synthesis of 7-hydroxy-4-vinylindole is also presented as an application of this method.

Asymmetric catalysis under almost-neutral reaction conditions is key for the efficient synthesis of optically active polar molecules. We have developed catalytic enantioselective reactions of acyclic or cyclic alkenyl esters by using an (S)-BINOL-derived chiral tin-dibromide reagent that possesses a bulky aryl group at the 3 or 3′ position as the chiral pre-catalyst in the presence of a sodium alkoxide and an alcohol, in which a chiral tin alkoxide bromide is generated in situ and recycled with the assistance of an alcohol. In this Personal Account, we describe three types of asymmetric transformation that proceed through a chiral tin enolate: 1) The asymmetric aldol reaction of alkenyl esters or unsaturated lactones with aldehydes or isatins; 2) the asymmetric three-component Mannich-type reaction of alkenyl esters and related cycloaddition reactions; and 3) the asymmetric N-nitroso aldol reaction of unsaturated lactones with nitrosoarenes.

The enantio- and diastereoselective cross-annulation of cinnamaldehyde (6) and 2,2,2-trifluoroacetophenone (7) was examined to evaluate the performance of newly developed chiral bicyclic imidazoliu...

A catalytic enantioselective Mannich-type reaction of a cyclohexanone-derived alkenyl trichloroacetate with isatin imines was achieved using an (S)-BINOL-derived chiral tin dibromide possessing a 4-tert-butylphenyl group at 3- and 3′-positions as the chiral precatalyst in the presence of sodium methoxide, sodium iodide, and methanol. Optically active 3-alkylated 3-amino-2-oxindoles having up to 90% enantiomeric excess were diastereoselectively obtained in high yields under the influence of the in situ generated chiral tin iodide methoxide.

A diverse series of chiral bicyclic NHC/Ir complexes were prepared via a previously developed divergent synthesis of chiral imidazolium salts. Among the complexes, 8dz was found to be an excellent catalyst precursor for the Ir-catalyzed asymmetric transfer hydrogenation of ketones. The reaction of ketones with 8dz proceeded smoothly to give corresponding alcohols with high enantioselectivities (up to 98%) and productivities (TON up to 4500).

A catalytic enantioselective aldol reaction of alkenyl esters with isatins was achieved using an (S)-BINOL-derived chiral tin dibromide possessing a 4-tert-butylphenyl group at 3- and 3′-positions as the chiral pre-catalyst in the presence of sodium methoxide and methanol. Optically active 3-alkylated 3-hydroxy-2-oxindoles having up to 98% ee were diastereoselectively obtained in high yields not only from cyclic alkenyl esters but also from acyclic ones under the influence of the in situ generated chiral tin bromide methoxide.

The selective synthesis of substituted indoles was achieved by the ring-closing olefin metathesis (RCM)/elimination sequence or the RCM/tautomerization sequence of functionalized pyrrole precursors. The RCM/elimination sequence was also applied to double ring closure to yield a substituted carbazole.

A new chiral zinc-amide 2s ′ was found to be an effective catalyst for the asymmetric addition of diethylzinc to aldehydes 3 through a screening method for asymmetric catalysts, in which two catalytic asymmetric reactions are connected. The chiral zinc catalyst can be readily prepared catalytically from achiral imine 1 by the chiral rhodium–diene complex mediated asymmetric addition of dimethylzinc.

The deleterious effect of ethylene gas on the ring-closing olefin metathesis (RCM) for the formation of 5- to 8-membered rings was investigated. Significant rate differences caused by ethylene gas were observed among the different ring-size formation reactions. Nevertheless, the rate differences can be advantageously utilized for chemoselective RCM.

A novel reaction involving cyano transfer from benzophenone cyanohydrin to aldehydes and imines was realized by using dibutyltin dimethoxide as a catalyst. Various cyanohydrins and α-amino nitriles were obtained in moderate to high yields by this reaction. Ketimines also showed remarkable reactivity as cyano acceptors under conventional reaction conditions. This catalytic reaction was further applied to a three-component condensation reaction of aldehydes, aniline, and benzophenone cyanohydrin in the presence of Drierite ® .

A Barbier-type propargylation of azo compounds with γ-trialkylsilylated propargylic bromides has been achieved using reactive barium as a low-valent metal in THF. Corresponding propargylated hydrazines (α-adducts) were exclusively formed not only from azobenzenes (diaryldiazenes) but also from dialkyl azodicarboxylates. This method is also applicable to γ-alkylated or γ-phenylated propargylic bromides, providing the desired propargylated products only.

Harvesting the radial forearm flap may cause circulatory problems in the donor arm. To investigate the influence on donor hands after radial forearm flap harvesting, we assessed the process of circulatory changes prospectively by measuring skin perfusion pressure (SPP) that is clinically useful in detecting vascular lesions. The records of 17 patients (14 men and 3 women aged 59.7+/-11.8 years) who had undergone free radial forearm flap transfer for head and neck reconstruction, between December 2005 and April 2007, were analysed. SPP in the thumb (finger I), the middle finger (III) and the little finger (V) was measured in the 17 patients preoperatively and 1 month and 3, 6, 9 and 12 months postoperatively. All statistical tests were two sided, with a significance level defined as p

A novel aldol reaction of alkenyl trichloroacetates with α-keto esters was realized by using dibutyltin dimethoxide as a catalyst, which was regenerated by the addition of methanol. The reaction was found to be remarkably accelerated by the addition of a catalytic amount of a bidentate phosphine⋅silver(I) complex. Use of the BINAP⋅silver triflate (AgOTf) complex as the chiral co-catalyst resulted in the formation of optically active aldol products possessing a chiral tertiary carbon with up to 93% ee. This catalytic method was further applied to the asymmetric reaction of diketene with methyl benzoylformate.

Nitrosoaldol reaction between alkenyl trichloroacetates and nitrosobenzene has been achieved using dibutyltin dimethoxide as a catalyst, which is regenerated in the presence of methanol. The corresponding α-hydroxyamino ketones (N-adducts) have exclusively formed not only from cyclic alkenyl trichloroacetates but also from acyclic ones.

The demand for functionalized aromatic compounds is growing rapidly in many research fields. Therefore, the efficient synthesis of desired aromatic compounds is a critical issue in organic synthesis. In this account, we describe new synthetic approaches to versatile aromatic compounds, such as phenols, benzenes, 3-hydroxypyridines, and styrenes, by ring-closing olefin metathesis (RCM)/aromatization and ring-closing enyne metathesis (RCEM)/aromatization of acyclic precursors. The advantages in terms of simplicity, flexibility, and avoidance of the formation of regioisomers are proof of the versatility of this method for the synthesis of aromatic compounds.

New synthetic routes to substituted 3-hydroxypyridines 6 are presented. Ring-closing olefin metathesis (RCM)/elimination and RCM/oxidation/deprotection of nitrogen-containing dienes 4 are the key processes of the routes. An application of RCM/oxidation/deprotection to the synthesis of 3-aminopyridine 13f is also described.

A library of imidazoline-aminophenol ligands was synthesized on solid supports. After immobilization of chiral chloromethylimidazolines 1 and 2 onto the polystyrylsulfonyl chloride, nucleophilic substitution with (R)- or (S)-phenylethylamine (3 and 4) provided four combinations of polymer-supported imidazoline-amine ligands. Further reductive alkylation using salicylaldehydes 7-10 provided a series of imidazoline-aminophenol ligands (L9-L24). Analysis by solid-phase catalysis/circular dichroism high-throughput screening of a copper-catalyzed Henry reaction revealed that ligand L25, comprising a (S,S)-diphenylethylenediamine-derived imidazoline, (S)-phenylethylamine, and dibromophenol, was highly efficient, thus providing the adduct of nitromethane and benzaldehyde in 95 % ee. The combination of stereogenic centers was crucial in promoting the highly stereoselective reactions. The unique reaction sphere of L25 was also examined in a Friedel-Crafts alkylation of indole and nitroalkene to give the adduct in up to 83 % ee.