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Highlights • A novel series of supramolecular catalysts were prepared and characterized by NMR, FT-IR, TEM, XRD, TGA, and XPS. • A picolinamide-modified β-cyclodextrin/Pd(II) complex showed very efficient catalytic activity for Suzuki-Miyaura coupling. • A proposed mechanism of the Pd(II)/Pd(IV) catalytic cycle was explored and calculated by ab initio QM/MM methods. • This hydrosoluble catalyst can be reused several times without a significant loss of activity. Abstract Novel supramolecular catalysts for Suzuki-Miyaura coupling were prepared and characterized by NMR, FT-IR, TEM, XRD, TGA, and XPS. The resulting picolinamide-modified β-cyclodextrin/Pd(II) complex (Pd(II)@PCA-β-CD) showed very efficient catalytic activity for Suzuki-Miyaura coupling of aryl, benzyl, and allyl halides with arylboronic acids in an environmentally benign aqueous solution. Various organic halides including chlorides can produce good to excellent yields with phenyl-boronic acid and a catalytic amount of Pd(II)@PCA-β-CD. This hydro-soluble catalyst was capable of being reused for at least eight runs with only a slight loss of catalytic activity. A putative mechanism of the Pd(II)/Pd(IV) catalytic cycle was also explored and calculated by ab initio QM/MM methods. [ABSTRACT FROM AUTHOR]

Lignin is one of the major macromolecule in nature that contains an aromatic ring structure, and also a potential source of high-value products such as biofuels and chemicals. However, Lignin is a kind of complex heterogeneous polymer which can produce many degradation products during processing or treatment. These degradation products are difficult to separate, making it challenging to use lignin directly for high-value applications. This study proposes an electrocatalytic method to degrade lignin by using allyl halides to induce double-bonded phenolic monomers, while avoiding separation. In an alkaline solution, the three basic structural units (G, S, and H) of lignin were transformed into phenolic monomers by introducing allyl halide, which could effectively expand lignin application space. This reaction was achieved using a Pb/PbO 2 electrode as the anode and copper as the cathode. It was further confirmed that double-bonded phenolic monomers were obtained by degradation. 3-allylbromide has more active allyl radicals and significantly higher product yields than 3-allylchloride. The yields of 4-allyl-2-methoxyphenol, 4-allyl-2,6-dimethoxyphenol and 2-allylphenol could reach 17.21 g/kg-lignin, 7.75 g/kg-lignin, and 0.67 g/kg-lignin respectively. These mixed double-bond monomers can be used as monomer materials for in-situ polymerization without further separation, which lays the foundation for high value-added applications of lignin. [ABSTRACT FROM AUTHOR]

Et 3 B/O 2 -mediated radical coupling reactions of O,Te-acetal 2 were explored using diverse electrophilic double bonds. Ethyl radical derived from Et 3 B under air cleaved the C–Te bond of 2 to generate α-alkoxy bridgehead radical I , which reacted with cycloalkenones, cycloalkylidenemalononitriles, allyl halides, and imines at or below ambient temperature. These intermolecular reactions from O,Te-acetal 2 were mild and versatile, and were superior to those of O,Se-acetal 1 in terms of efficiency and substrate scope. A total of 14 new and nine improved coupling reactions are described, all of which realized the installation of the functionalized carbon units at the sterically hindered bridgehead position of trioxaadamantane. [ABSTRACT FROM AUTHOR]

The reaction of tin(II) and tin(IV) mono- o -amidophenolate complexes based on redox-active 4,6-di- tert -butyl-N-(2,6-di- iso -propylphenyl)-o-aminophenol ( dipp APH 2 ) with allylhalides is reported. This process includes oxidative addition of all-Hal (where all = allyl, Hal = Cl, Br, I) molecule to the non-transition metal complex and results in the alkyl transfer to carbon ring with the formation of new C C coupled product. The interaction proceeds at room temperature and gives new tin(IV) derivatives containing iminocyclohexa-1,4-dienolate ligand. The “oxidative addition” type products have been characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and characterization of the new bis-o-amidophenolate gallium(III) complex are reported. This compound was found to be reactive towards allyl halides at room temperature. The addition of two allyl halide molecules to the original complex accompanied with two new C–C bonds formation has been observed. The structures of the products obtained were confirmed by 1H NMR and X-ray diffraction analysis. [Copyright &y& Elsevier]

Abstract: A mild and operationally simple approach to highly functionalized oxazolones has been developed, which involves an intramolecular oxypalladation of N-alkynyl tert-butyloxycarbamates, followed by either protonolysis of the alkenyl C–Pd bond to afford 3,5-disubstituted oxazolones or allylation with allyl halides in the presence of Ag2CO3 to generate 3,4,5-trisubstituted oxazolones, respectively. [Copyright &y& Elsevier]

Abstract: An investigation was conducted to determine whether the cross-metathesis (CM) of allyl halides tolerates amide groups. The results show that the ruthenium-based complexes I–III serve as poor catalysts for the CM of allyl halides with olefins that contain an N,N-dimethylamide group. In contrast, the Grubbs–Hoveyda–Blechert second generation catalyst (III) efficiently promotes these processes with olefins bearing a Weinreb amide group. Lastly, a reinvestigation of the ester group tolerance of the allyl halide CM with unsaturated esters demonstrated that III serves as an efficient catalyst for these reactions. [Copyright &y& Elsevier]

Abstract: New α-silylacetic acids have been prepared following a general and convenient procedure of a one-pot reaction between trimethylsilylacetate and different chlorosilanes. New derivatives of diphenyl(methyl)silylacetic acid were prepared by a direct alkylation of its dianion with benzyl-, allyl-, and alkyl halides and trimethylchlorogermane to afford new α-silylcarboxylic acids. [ABSTRACT FROM AUTHOR]

Abstract: The C-6 unit of methyl α-d-galactopyranoside was selectively modified by combining enzymatic oxidation with an indium-mediated allylation reaction. The Barbier–Grignard type reaction, where a carbonyl group reacts with an allyl halide, proceeds in aqueous solution, even with water as the only solvent; thus carbohydrates can be modified without the need for drying or protection–deprotection steps. The corresponding homoallyl alcohols are produced in high yields of >90% in the reactions with allyl bromide and cinnamyl chloride. The main products were isolated and characterized by GC–MS and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: In the present work the stereocontrolled palladium-catalysed umpolung allylation of aldehydes is described. Allyl acetates are in situ transformed into the corresponding allyl boronates, which directly react with aldehydes. The question of stereocontrol is raised by employing (a) chiral boronating agents (reagent control) and by (b) utilising chiral aldehydes (substrate control). These studies reveal that the approach based on substrate control is superior to the former one with respect to yields and stereoselectivity. Remarkably, this umpolung protocol often yields the 4,5-syn products in high selectivity, which is unprecedented for direct crotylations. [ABSTRACT FROM AUTHOR]

Abstract: A protocol for the generation of allyl Grignard reagents via the catalytic activation of allyl halides is described herein. Subsequent nucleophilic addition to carbonyl derivatives provided the desired homo allylic alcohols in excellent yields (84–99%). Evidence suggests that titanocene dichloride catalyzes the formation of an allyl Grignard species which reacts solely with the carbonyl electrophile as evidenced by the complete absence of Würtz coupling. This methodology will have wide-ranging applicability in the generation of highly reactive organometallic reagents. [Copyright &y& Elsevier]

Abstract: (S)-4-Methyl-3,6-dihydro-2H-pyran-2-carbaldehyde (3), the common intermediate in the syntheses of the C17–C27 subunit of laulimalide (4) and (+)-faranal (5), the trail pheromone of the pharaoh ant, Monomorium pharaonis, were obtained via transformation of methyl 3-bromomethyl-3-butenoate (1) into allylstannane 2 and subsequent allylation of (benzyloxy)acetaldehyde (6) in accordance with the Keck procedure as the key steps. [Copyright &y& Elsevier]

Abstract: We describe herein an extension of the halogenation of 1,2 or 1,3-diols via a cyclic thionocarbonate functionality by reaction with an allyl halide instead of methyl iodide, which is usually used. This investigation was successfully carried out under both conventional heating and microwave solvent-free conditions with some alditol, thioanhydroalditol, and aldose derivatives. [Copyright &y& Elsevier]

Abstract: A facile method to obtain novel sucrose polymers is reported. These polymers were obtained by means of the Thiol-Ene photopolymerization technique. The sucrose was functionalized with allyl groups by etherification with allyl bromide and then photopolymerized by the step-growth mechanism with multifunctional thiols. The kinetics of photopolymerization were determined by optical pyrometry and Real-Time FT-IR. It was found that this photocurable system was highly reactive obtaining solid crosslinked polymers that displayed high uniformity in the crosslink density. A T g of 58°C was determined by means of DMA for the polymer derived from A2S and PETKMP. The prepared polymers displayed thermal stability up to 230°C. [Copyright &y& Elsevier]

Abstract: Previous studies have demonstrated that the silver hydride cluster cation Ag4H+ promotes Cupling of allylbromide [G.N. Khairallah, R.A.J. O’Hair, Angewandte Chemie International Edition 44 (2005) 728]. Here the influence of both the nature and the size of the silver cluster cation and the substrate on Cupling are examined. Thus each of the cations Ag2H+, Ag4H+, Ag3 +, and Ag5 + were allowed to react with three different halides: allyl chloride, allyl bromide and allyl iodide. No Cupling is observed in the reactions of the cluster cations with allyl chloride. There are four main reaction sequences that result in Cupling for allyl bromide and allyl iodide mediated by Ag n + and Ag n−1H+ clusters: [(i)] A sequence involving the reactions of silver cluster cations with two molecules of C3H5X: Ag n + →Ag n (C3H5X)+ →Ag n X2 +. This only occurs in the cases of: n =3 and X=I; n =5 and X=Br. [(ii)] A sequence involving the reactions of silver cluster cations with two molecules of C3H5X via an organometallic intermediate: Ag n + →Ag n−1(C3H5)+ →Ag n−1X+. This only occurs in the cases of: n =5 and X=Br and I. [(iii)] A sequence involving the reactions of silver hydride cluster cations with three molecules of C3H5X: Ag n−1H+ →Ag n−1X+ →Ag n−1X(C3H5X)+ →Ag(C3H5)2 + and Ag n−1X3 +. This only occurs in the cases of: n =5 and X=Br and I. [(iv)] A sequence involving the reactions of silver hydride cluster cations with three molecules of C3H5X via an organometallic intermediate: Ag n−1H+ →Ag n−1X+ →Ag n−3(C3H5)+ →Ag(C3H5)2 + and Ag n−3X+. This only occurs in the cases of: n =5 and X=I. [Copyright &y& Elsevier]

Abstract: Efficient syntheses of both enantiomers of the C13–C21 fragment of epothilone molecules have been performed by use of enantiomeric oxiranyl-substituted cyclopropylsulfonates as key intermediates. The latter were obtained by the cyclopropanation of easily available (R)-methyl 2,3-O-isopropylideneglycerate and subsequent manipulation of the functional groups. Asymmetric allylation of 1-formylcyclopropyl pivalate led to an alternative precursor of the target compounds with moderate enantioselectivity. [Copyright &y& Elsevier]

Abstract: The carbonylative addition between allyl halides and alkenes is described. The [2+2+1] reaction is catalyzed by Ni(I), and takes place with different strained alkenes under very mild conditions. Changes in solvent and use of different amounts of water in the reaction produce changes on the final products obtained. [Copyright &y& Elsevier]

Abstract: 4-Allyl-phosphaisoquinolin-1-ones were synthesized by palladium-catalyzed coupling–cyclization of o-ethynylphenylphosphonamide monoethyl esters with allyl halides with high regioselectivity and good yields. The synthesized 4-allyl-phosphaisoquinolin-1-ones show bioactivity as inhibitor of MCH-1R. [Copyright &y& Elsevier]

Much evidence in the last few years suggests that the antiproliferative effects of various garlic secondary metabolites in in vitro experimental systems are due to redox-based mechanisms. In particular, sulfur-containing allyl compounds have been demonstrated to generate reactive oxygen species and to modify directly the redox state of specific reactive cysteines on protein surfaces. On the basis of such properties, allyl compounds, in particular the ones present in the oil-soluble fraction of garlic extracts, can function as modulators of several redox-mediated signaling pathways related to the activation of mitogen-activated protein kinases, cell cycle, DNA repair, and cell demise. However, even though many in vitro studies have tried to dissect the mechanisms of action of garlic derivatives, research in this field is still incomplete and questions about bioavailability, biotransformation, and pro-oxidant activity are still unanswered. This review discusses recent findings on such aspects, focusing on the chemistry of allyl compounds and their preferential cellular targets as well as on related nutritional aspects. [ABSTRACT FROM AUTHOR]

Abstract: The new 6-deoxy-d-allal- and 6-deoxy-d-galactal-derived allyl epoxides 8α and 8β have been stereoselectively prepared and their behaviour as glycosyl donors in addition reactions with nucleophiles examined and compared with that of the corresponding 6-OR (R=Bn, Tr) substituted epoxides. The completely stereoselective substrate-dependent glycosylation process found in the reaction of 8α and 8β with O-nucleophiles (alcohols and partially protected monosaccharides) and C-nucleophiles (alkyl lithium compounds and TMSCN), indicated that a 6-OR group in the side chain is not necessary for determining the selectivity. The reaction of 8α and 8β with azide (TMSN3, N-nucleophile) made it possible to revise a previously proposed rationalization for the formation of the corresponding cis-azido alcohol (syn-1,2-addition product). [Copyright &y& Elsevier]

Abstract: We have identified silver tetrafluoroborate (AgBF4) as an excellent promoter for the activation of various glycosyl donors including glycosyl halides, trichloroacetimidates, and thioimidates. Easy handling and no requirement for azeotropic dehydration prior to application makes AgBF4 especially beneficial in comparison to the commonly used AgOTf. Selective activation of glycosyl halides or thioimidates over thioglycosides or n-pentenyl glycosides, including simple sequential one-pot syntheses, has also been demonstrated. Versatility of glycosyl thioimidates was further explored by converting these intermediates into a variety of other classes of glycosyl donors. [Copyright &y& Elsevier]

Abstract: Synthesis of a series of chromene[4,3-b]pyrroles has been accomplished through an intramolecular 1,3-dipolar cycloaddition reaction of an azomethine ylide with the dipolarophile derived from Baylis–Hillman adducts. Improved yields of the same products were obtained when the reaction was carried out under ultrasonication. [Copyright &y& Elsevier]

We present data collected from a number of snow-covered environments including two polar locations (Summit, Greenland and the South Pole) and two mid-latitude regions (a remote site in northern Michigan, and Niwot Ridge, Colorado). At each site, concentrations of and were enhanced within the interstitial air near the snow surface, compared to levels in boundary layer air. Fluxes of from surface snow to the atmosphere were observed at each site except Niwot Ridge, where appeared to have a sink. The mid-latitude sites showed significant emissions of , mostly originating at the ground surface and traveling up through the snow, while at the polar locations emissions from firn air were relatively small. In general, methyl halide mixing ratios in firn air were significantly greater at Summit than at the South Pole, with Summit showing a strong diurnal cycle in the production of alkyl halides that was well correlated with actinic radiation and firn temperature. We suggest that the most likely route to alkyl halide formation is through an acid catalyzed nucleophilic substitution of an alcohol type function by a halide, both of which should be preferentially segregated to the quasi-liquid layer at the surface of the snow grains. A series of experiments using a snow-filled quartz chamber irradiated by natural sunlight allowed estimation of emission trends that were hard to measure in the natural snowpack. These static chamber experiments confirmed significant production of the primary alkyl halides, following the order . Our observations at all four locations, including polar and mid-latitude sites, imply that alkyl halide production may be associated with all surface snows. [Copyright &y& Elsevier]

Abstract: The asymmetric allylation reactions of aldehydes catalyzed by a 10mol% bisoxazoline complex bearing a phosphine oxide moiety, which was newly designed and synthesized from l-serine, afforded the corresponding homoallylic alcohols in 48–74% yields with 39–86% ee. The reaction proceeds with the dual activation of the aldehyde and allylsilane by the Lewis acid and base of the catalyst. The evidence for the activation of the allylsilane was clarified by the 31P NMR spectra. [Copyright &y& Elsevier]

Abstract: A novel class of thiacrown and azacrown ethers incorporating the 1,7-dioxaspiro[5.5]undecane spiroacetal ring system was prepared by reaction of ditosylate 5 with the appropriate dithiols 9a–c or protected diamine 12a. Spiroacetal ditosylate 5 in turn, was prepared from diol 3 via ozonolysis of bisallyl ether 7 followed by tosylation of the derived diol 8. [Copyright &y& Elsevier]

Abstract: The palladium-catalyzed allylation of aryl halides with homoallyl alcohols via retro-allylation proceeds at 200–250°C in a toluene–DMF mixed solvent using microwave heating. Even at such high temperatures, the regio- and stereospecificity of the allyl transfer reaction is still satisfactory. The amount of the palladium catalyst can be reduced to 0.5 or 0.05mol%. [Copyright &y& Elsevier]

Abstract: The free radical additions of fluorine-containing halides to 4-pentenamides initiated by Na2S2O4 were investigated. Both polyfluoroalkyl iodide and ethyl iododifluoroacetate, gave rise to fluorine-containing γ-butyrolactones as the main products while bromides such as ethyl bromodifluoroacetate gave the addition–reduction product. After steric and stereo effects on reaction yields were studied using various substrates, it was concluded that the reactions of 4-pentenamides and polyfluoroalkyl iodides provide one alternative approach to prepare γ-butyrolactones with fluorinated side chains. [Copyright &y& Elsevier]

Abstract: An efficient N-arylation of amines with aryl halides in presence of heterogeneous recyclable Cu–Fe–hydrotalcite catalyst has been developed. [Copyright &y& Elsevier]

Abstract: Novel aza-paracyclophane-oxazoline catalysts 4, 5 were produced from Vögtle’s R p-2-cyano-aza-paraclycophane and amino alcohols reacted with zinc chloride followed by m-chloroperbenzoic acid. 4′-Benzyl and tert-butyl-S and R-oxazoline variants were produced and explored as catalysts for asymmetric allylation of aldehydes using trichloroallylsilane. With R p,S-4a (R= tert-butyl) (1.5mol%) aromatic aldehydes reacted with high yields and selectivities, as with benzaldehyde (95%, 93% ee). R p,S-4b (R=benzyl) was superior with dihydrocinnamaldehyde (77%, 85% ee). [Copyright &y& Elsevier]

Abstract: The mechanism of the carbonylation reaction of allyl halides catalyzed by nickel (Ni(CO)4) and palladium (Cl2Pd(PPh3)2) complexes is theoretically investigated at the DFT level using the hybrid B3LYP functional. The favored reaction path to carbonylation corresponds, for both catalysts, to a direct attack of the halogen on the metal. This affords η1 intermediates that can undergo the final carbonylation step. It is also possible to obtain the acyl product (β,γ-unsaturated acyl halides) from η2 and/or η3 intermediates. However, in this case, the barrier of the rate-determining step to carbonylation is much higher. Since a channel on the potential surface connects rather easily the η2 or η3 intermediates to the η1 intermediates, an alternative and competitive path leading to the acyl products can originate from the η2 or η3 intermediates, follow the η2/η3 →η1 transformation, then undergo the final carbonylation step. [Copyright &y& Elsevier]

Abstract: A new strategy based on allylation of N-allylpyridin-2-ones with the lithium allyldibutylmagnesate reagent followed by ring-closing metathesis in a sequential fashion to access the quinolizidine skeleton with olefinic bonds in both rings is reported. [Copyright &y& Elsevier]

Abstract: Barbier type additions of allylic bromide 4, derived from (Z)-but-2-en-1,4-diol 2 to (R)-2,3-cyclohexylideneglyceraldehyde 1 were performed through mediation with Zn employing Luche’s procedure and also with low valent Cu, Co, and Fe which were produced via bimetal redox strategy in THF to afford 5c,d as the major products. From these, 5a,b were prepared following an oxidation–reduction protocol. Compound 5c was exploited as a representative starting material to develop a simple and inexpensive strategy toward the synthesis of 3′-C-branched 2′,3′-dideoxynucleosides having stereodiversity at 3′- and 4′-positions. [Copyright &y& Elsevier]

Abstract: Benzoxazoles 2 can be smoothly synthesized by treatment of starting materials of N-(2-hydroxyaryl) cyclopropyl amides 1 with PPh3/CCl4 in acetonitrile in good yields. When PPh3/CBr4/MS 4Å was used in the reaction system, the corresponding ring-expanding products 3 were obtained in moderate to good yields in acetonitrile at 80°C. Using DCE as a solvent in this reaction, the corresponding 2-(3-chloropropyl)benzoxazoles 5 were obtained as major products. [Copyright &y& Elsevier]

Abstract: The Sonogashira coupling reaction of aryl halides with a masked acetylene, leading to the formation of diarylethynes is reviewed. The process is either run in a sequential coupling–deprotection–coupling manner, or sometimes it is carried out in one-pot, a reaction we coined domino coupling. The procedures were also extended to the synthesis of compound libraries. [Copyright &y& Elsevier]

Abstract: The ρ values of free radical SH2′ reactions have been determined in various solvents. The correlation of Hammett ρ with Taft''s π* gives a W value of 0.70. The W value is a measure of susceptibility of the reaction constant to change in solvent polarity. However, the W value is 2.64 in the dissociation reactions of substituted benzoic acids. The free radical reactions are less susceptible to the solvent effect than ionic reactions and this could be rationalized in terms of the partial charge formed in the transition state of free radical reaction is less than that of heterolytic reaction. The ρ values in SH2′ reactions might not reflect truly the partial charge separation at transition state, however, it might be a measure of the susceptibility of the reaction to the electronic effect of the substituents. [Copyright &y& Elsevier]

Five different dinucleotides, each containing two allyl groups in various positions, were prepared and studied as substrates for ring-closing metathesis reactions. These dinucleotides were designed from appropriate nucleoside building blocks combining four different positions for the allyl group; the allyl phosphotriester linkage, 5-allyl-2′-deoxyuridine, and ribo- as well as arabino-configured 2′-O-allyluridine. Thus, convenient procedures for these building blocks were developed. From the dinucleotides, two new cyclic nucleotide structures were obtained; one connecting two adjacent nucleobase moieties and the other forming an unsaturated four-carbon linkage between the phosphate moiety and the adjacent pyrimidine nucleobase. The latter cyclic dinucleotide was also prepared with a saturated four-carbon linkage using a tandem ring-closing metathesis–hydrogenation procedure. This compound was found to be significantly more stable towards a nucleophilic ring-opening than its unsaturated counterpart. [Copyright &y& Elsevier]

A simple, mild and efficient stereoselective synthesis of (Z)- and (E)-allyl bromides and iodides has been developed by treatment of the Baylis–Hillman adducts with lithium bromide and iodide, respectively, in methylene chloride catalyzed by silica supported sodium hydrogen sulfate at room temperature. The role of various solvents, different reacting metallic halides, nature of the adducts and activity of several heterogeneous catalysts on the yields and stereochemistry of the products have been thoroughly studied. [Copyright &y& Elsevier]

Systematic studies were performed on SnCl2-mediated carbonyl allylation reaction between aldehydes and allyl halides in fully aqueous media. Totally three valuable reaction systems were discovered, which were SnCl2/CuCl2, SnCl2/TiCl3, and SnCl2/PdCl2. They all provided good to excellent yields in the allylation of aliphatic and aromatic aldehydes under very mild and convenient conditions. SnCl2, by itself, was also found to be effective for the allylation reaction when allyl bromide was employed. However, the SnCl2-only reaction could only tolerate very small amount of water as the solvent. The SnCl2/CuCl2, SnCl2/TiCl3, and SnCl2/PdCl2-mediated reactions exhibited good regioselectivity favoring the γ-adduct when cinnamyl halides were employed as the allylation reagent. The same reactions with cinnamyl halides also showed good diastereoselectivity favoring the anti-product. Mechanistic studies using proton NMR techniques suggested that the additive (i.e., CuCl2, TiCl3, PdCl2) could accelerate the formation of allyltin intermediate, but this step was shown not to be the most important for the allylation. Thus we proposed that the Lewis acid catalysis effect exerted by the additive was the main reason for the observed reactivity enhancement. [Copyright &y& Elsevier]

4-Phenylbut-3-enamide could be synthesized from corresponding 3-chloroprop-2-enylbenzene, carbon monoxide (1 atm), and titanium–nitrogen complexes, prepared from Ti(OiPr)4, Li, TMSCl, and molecular nitrogen (1 atm), using a palladium catalyst. The reaction proceeds via transmetalation of the titanium–nitrogen complex to an acylpalladium complex. PtBu3 as a ligand of the palladium catalyst, afforded a good result, and the amounts of Li and TMSCl affected the yield of amide. When the reaction was carried out using a bidentate ligand on the palladium complex under an atmosphere of argon instead of carbon monoxide, an allylamine derivative was obtained. [Copyright &y& Elsevier]

Chemical modification was carried out on disodium octoborate tetrahydrate (DOT)-treated wood using allyl glycidyl ether (AGE) in combination with methyl methacrylate (MMA) to limit boron leaching. Co-polymerization of the monomers in DOT-treated sugi (Cryptomeria japonica D. Don) wood was completed by catalyst heat treatment. Besides boron leachability, the dimensional stability and decay, and termite resistance of chemically modified wood were also determined. Dimensional stability in terms of anti-swelling efficiency and water absorption was found to improve in chemically modified wood specimens. Co-polymerization of AGE with MMA in DOT-treated wood resulted in less boron leaching compared with DOT-only-treated wood. Chemically modified wood containing boron proved to be more resistant to the brown-rot fungus Fomitopsis palustris (Berkeley et Curtis) Murrill (FFPRI 0507) and the white-rot fungus Trametes versicolor (L. ex Fr.) Quel. (FFPRI 1030) in laboratory decay resistance tests after severe leaching for 10 days. Termite resistance tests also showed that wood specimens treated with DOT and MMA plus AGE monomers were effective against subterranean termites Coptotermes formosanus Shiraki even after severe leaching cycles. [Copyright &y& Elsevier]

From the readily available allylic alcohols or allylic amines, a novel Pd(II)–CuCl2-catalyzed haloamination reaction of alkenes with high chemo-, regio-, and diastereo-selectivity was developed. The reaction proceeds through trans-aminopalladation of alkenes, followed by oxidative cleavage of the carbon–palladium bond with retention of configuration. [Copyright &y& Elsevier]

Nucleophilic substitution reactions of highly functionalized allyl halides with three anions, N3−, AcO−, and PhSO2−, in ionic liquid media were conducted. The ionic liquid, [Bmim][BF4], was found to be superior to classical organic solvents to give higher yields and faster reaction rates. The resulting products belong to multifunctionalized trisubstituted α,β-unsaturated ketones, which are useful building blocks for organic synthesis. [Copyright &y& Elsevier]

A mild protocol for diastereoselective allylations and crotylations of α- and β-silyloxy substituted aldehydes utilizing potassium allyl/crotyltrifluoroborates is described. The reactions proceed to completion within 30 min at room temperature in biphasic or aqueous media in the presence of a phase transfer catalyst. The resulting homoallylic alcohols are obtained in high yields and moderate to excellent diastereoselectivities. The method was applied to the asymmetric total synthesis of the antiobesity agent tetrahydrolipstatin (orlistat™). [Copyright &y& Elsevier]

The allylic fluorides 1 and 2 are used as models to study the effect of the allylic C–F bond on the diastereoselectivity of reactions occurring on the vicinal double bond, as well as the compatibility of this C–F bond with various reagents. The configurational stability of the Z double bonds in enals and enones 1 and 3 is noteworthy. This allowed us to perform various types of reactions (including thermal Diels–Alder cycloadditions) on derivatives 1 with full control of the Z geometry. [Copyright &y& Elsevier]

Free-radical mediated cyclopropane ring opening of 2-silylbicyclo[3.1.0]hexane 1 has been carried out leading to the corresponding trisubstituted cyclopentenes 5 and 6 in good yield with complete 1,2-stereocontrol. [3+2]-Annulation has also been performed by trapping the resulting radical with electron-rich and electron-poor olefins, leading to the corresponding polycyclic compounds. Further studies on the functionalisation of dihydropyridines and pyrroles using this methodology is also described. [Copyright &y& Elsevier]

A four-step cyclopentenone annulation reaction of allylic alcohols employing a 5-exo-trig radical cyclisation reaction of mixed allyl methyl ketals of bromoacetone as the key step is described. The annulated product 12b obtained from 2,3-dimethylcyclohexenol has been further elaborated into (±)-epibakkenolides employing a 5-exo-dig radical cylisation reaction based α-spiro-β-methylene-γ-butyrolactone annulation methodology. [Copyright &y& Elsevier]

Alkylation of dienediolates from unsaturated carboxylic acids with allylic halides when followed by solventless thermal treatment at 150 to 200°C afford rearranged products on a trend highly dependent on the α carbon substitution. Thus, 2,2-bisallylated acids with H atoms at C-2 lead to its 1,3-shift, whereas 2-methyl-2,2-bisallylated acids lead to the corresponding Cope rearrangement product. In the latter case, this tandem allylation-Cope reaction lead, in a highly regio and diastereoselective way, to products not accessible from direct alkylation. B3LYP/6-31G* energies for the compounds involved at these isomerizations are in reasonable agreement with the experiments, allowing to explain the formation of the more stable product under thermodynamic equilibrations. [Copyright &y& Elsevier]

Polymer-supported allylboron reagents have been prepared from triallylboranes and polymer-supported N-sulfonylamino alcohol. These polymeric reagents were reacted with arylimines to give the corresponding secondary homoallylic amines in high yields. Chloromethylated polystyrene was modified into the polymer-supported imine by the reaction with arylimines under phase transfer catalyzed conditions. This polymer was evaluated for its utilization in polymer analogue conversions. The recycleability of the polymeric ligand was also demonstrated. [Copyright &y& Elsevier]

Bromination and iodination of hydrosilanes and germanes were studied. Treatment of hydrosilanes with an excess of ethyl, propyl, or allyl bromide in the presence of a catalytic amount of PdCl2 or NiCl2 gave bromosilanes in good to high yield by hydrogen–halogen exchange. By using methyl, propyl, or allyl iodide as the iodine source, similar iodination of hydrosilanes was readily performed. Halogenation of hydrogermanes also proceeded by similar treatment. [Copyright &y& Elsevier]