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The nature of the substituents on cyclopropenes and catalysts could have a profound effect on the reactivity and selectivity of ring-opening metathesis polymerization (ROMP).

Products of main group elements from cross-coupling reactions have been shown to serve as Lewis acids, mediating further reactions of organic coupling products. Thus, the nickel-catalysed olefination of benzylic dithioacetal with MeMgI in benzene in a sealed Schlenk tube at 130 °C generates magnesium mercaptide which regioselectively converts 2-arylpropene into a dimer in good yield. Aryl iodide reacts with 2-propenylmagnesium bromide in the presence of 1,2-ethanedithiol and NiCl

Epoxy composites filled with both graphene oxide (GO) and diglycidyl ether of bisphenol-A functionalized GO (DGEBA–f–GO) sheets were prepared at different filler loading levels. The correlations between surface modification, morphology, dispersion/exfoliation and interfacial interaction of sheets and the corresponding mechanical and thermal properties of the composites were systematically investigated. The surface functionalization of DGEBA layer was found to effectively improve the compatibility and dispersion of GO sheets in epoxy matrix. The tensile test indicated that the DGEBA–f–GO/epoxy composites showed higher tensile modulus and strength than either the neat epoxy or the GO/epoxy composites. For epoxy composite with 0.25 wt% DGEBA–f–GO, the tensile modulus and strength increased from 3.15 ± 0.11 to 3.56 ± 0.08 GPa (∼13%) and 52.98 ± 5.82 to 92.94 ± 5.03 MPa (∼75%), respectively, compared to the neat epoxy resin. Furthermore, enhanced quasi-static fracture toughness ( K IC ) was measured in case of the surface functionalization. The GO and DGEBA–f–GO at 0.25 wt% loading produced ∼26% and ∼41% improvements in K IC values of epoxy composites, respectively. Fracture surface analysis revealed improved interfacial interaction between DGEBA–f–GO and matrix. Moreover, increased glass transition temperature and thermal stability of the DGEBA–f–GO/epoxy composites were also observed in the dynamic mechanical properties and thermo-gravimetric analysis compared to those of the GO/epoxy composites.

Diphenylamino- and triazole-endcapped fluorene derivatives which show a wide energy band gap, a high fluorescence quantum yield and high stability have been synthesized and characterized. Single-layer electroluminescent devices of these fluorene derivatives exhibited efficient deep blue to greenish blue emission at low driving voltage. The single-layer OLED of PhN-OF(1)-TAZ shows a maximum current efficiency of 1.54 cd/A at 20 mA cm−2 with external quantum efficiency (EQE) of 2.0% and CIE coordinates of (0.153, 0.088) in deep blue region, while the single-layer device of oligothienylfluorene PhN-OFOT-TAZ shows a maximum brightness of 7524 cd/m2 and a maximum current efficiency of 2.9 cd/A with CIE coordinates of (0.20, 0.40) in greenish blue.

In this work, we developed a strategy to balance the toughness and thermal resistance of epoxy composites by incorporating the multi-scale rubber particles. Two types of rubber i.e. the phase-separation-formed submicron liquid rubber (LR) and preformed nano-scale powered rubber (PR) particles were chosen as tougheners. It was found that the combination of these multi-scale rubber particles not only provides superior efficiency in enhancing the impact resistance of epoxy composites, but also results in balanced glass transition temperature. In particular, the highest gain in impact strength was obtained for the ternary composites containing 9.2 wt% submicron liquid rubber and 9.2 wt% nano-sized powered rubber which were ∼112% higher than the maximum enhancements of ∼49% and ∼66% for the corresponding binary composite systems with the single-phase rubber, respectively. The damage zone observation and fracture surface analysis suggested that the combined use of multi-scale particles was effective to promote matrix plastic deformation including void growth and shear banding induced by the improved rubber cavitation/debonding, which is likely responsible for the highly improved impact resistance of the ternary composites.

The effect of dispersion state of graphene on mechanical properties of graphene/epoxy composites was investigated. The graphene sheets were exfoliated from graphite oxide (GO) via thermal reduction (thermally reduced GO, RGO). Different dispersions of RGO sheets were prepared with and without ball mill mixing. It was found that the composites with highly dispersed RGO showed higher glass transition temperature ( T g ) and strength than those with poorly dispersed RGO, although no significant differences in both the tensile and flexural moduli are caused by the different dispersion levels. In particular, the T g was increased by nearly 11 °C with the addition of 0.2 wt.% well dispersed RGO to epoxy. As expected, the highly dispersed RGO also produced one or two orders of magnitude higher electrical conductivity than the corresponding poorly dispersed RGO. Furthermore, an improved quasi-static fracture toughness ( K IC ) was measured in the case of good dispersion. The poorly and highly dispersed RGO at 0.2 wt.% loading resulted in about 24% and 52% improvement in K IC of cured epoxy thermosets, respectively. RGO sheets were observed to bridge the micro-crack and debond/delaminate during fracture process due to the poor filler/matrix and filler/filler interface, which should be the key elements of the toughening effect.

Both the irreversible agglomeration of graphene sheets and poor sheet/matrix interface are obstacles to obtain the desired properties of graphene/polymer composites. Herein, we fabricated epoxy composites with highly dispersed graphene via a facile surfactant-assisted process, and investigated the correlations between surface modification, morphologies, dispersion, re-agglomeration behaviour and interfacial interaction of graphene and the corresponding thermal and mechanical properties of the composites. It is found that the surfactant treatments of graphene are effective to improve their dispersion stability in water and inhibit their re-agglomeration during the curing of resin. Scanning and transmission electron microscopy analysis demonstrates that the dispersion/exfoliation level of graphene in the composites is greatly improved after surface treatments. These above ameliorating effects along with improved interface between the matrix and graphene arising from the hydrophilic and hydrophobic molecules of non-ionic surfactant result in increased tensile properties compared with those without surface modification. Moreover, the thermal stability of the graphene/epoxy composites is slightly enhanced over that of neat epoxy.

The attainment of both high toughness and superior electrical conductivity of epoxy composites is a crucial requirement in some engineering applications. Herein, we developed a strategy to improve these performances of epoxy by combining the multi-wall carbon nanotubes (MWCNTs) and spherical particles. Two different types of spherical particles i.e. soft submicron-rubber and rigid nano-silica particles were chosen to modify the epoxy/MWCNT composites. Compared with the binary composites with single-phase particles, the ternary composites with MWCNTs and spherical particles offer a good balance in glass transition temperature, electrical conductivity, stiffness and strength, as well as fracture toughness, exhibiting capacities in tailoring the electrical and mechanical properties of epoxy composites. Based on the fracture surface analysis, the complicated interactions between multiscale particles and the relative toughening mechanisms were evaluated to explain the enhancement in fracture toughness of the ternary composites.

A straightforward synthetic transformation of tertiary amines to the esterification of equimolar amounts of acids was demonstrated in this manuscript. The present protocol can be regarded as a straightforward synthetic transformation of tertiary amines to the esterification of equimolar amounts of acid. Moreover, the reaction is fundamentally new chemistry for the sp 3 C–N bond cleavage coupled with esterification. The esterification reaction conditions are very mild and functional group-tolerated, such as hydrosilanes, alcohols, phenol, and amino acids. A mechanism is proposed in which the tertiary amine reacts with dimethyl but-2-ynedioate to form zwitterionic salt, and then the zwitterionic intermediate subsequently accept hydrogen to assist the nucleophilic attack of oxygen atom of carboxyl group at the benzyl group of tertiary amine, while a separate reaction pathway leads to esterification.

the National Natural Science Foundation of China (Nos. 20973051 and 21173064);Program for Excellent Young Teachers in Hangzhou Normal University (HNUEYT, JTAS 2011-01-014)

A series of linear 2,5-tetraphenylsilole-vinylene-type polymers were successfully synthesized for the first time. The tetraphenylsilole moieties were linked at their 2,5-positions through a vinylene bridge with p-dialkoxybenzenes to obtain polymer PSVB and with 3,6-carbazole to obtain polymer PSVC. For comparison, 2,5-tetraphenylsilole-ethyne-type polymer PSEB was also synthesized, in which the vinylene bridge of PSVB was replaced with an ethyne bridge. Very interestingly, the bridging group (vinylene or ethyne) had a significant effect on the photophysical properties of the corresponding polymers. The fluorescence peak of PSEB at 504 nm in solution originated from the emission of its silole moieties, whereas PSVB and PSVC emitted yellow light and no blueish-green emission from the silole moieties was observed, thus demonstrating that the emissions of PSVB and PSVC were due to their polymer backbones. More importantly, the 2,5-tetraphenylsilole-ethyne polymer exhibited a pronounced aggregation-enhanced emission (AEE) effect but the 2,5-tetraphenylsilole-vinylene polymer was AEE-inactive. Moreover, both AEE-active 2,5-tetraphenylsilole-ethyne polymer and AEE-inactive 2,5-tetraphenylsilole-vinylene polymers were successfully applied as fluorescent chemosensors for the detection of explosive compounds.

In the present work, a new method for the analysis of the substituent group content in silicones by automatic elemental analyzer has been developed. Because of the number of substituent group effect on the physical and chemical properties about polysiloxane very much, its analysis by traditional techniques is tedious and costly. The novelty of this study relies on the fast and universal application of the automatic elemental analyzer to the quantitative analysis of the substituent groups. With this purpose, analysis of the quality percentage content of C and H in four different kinds of difunctional polysiloxane in automatic elemental analyzer, then compute the formula weight of a basic structure unit to deduce the content of the substituent group. The result was validated by 1H NMR.

In this paper, PA 66 were solution blended with poly(vinyl pyrrolidone)(PVP), an amorphous polar polyamide. The thermal behaviors and morphology in the blends of polyamides (PA66)) and PVP were investigated by WAXD, DSC, FT-IR and POM methods. The equilibrium melting temperatures for PA 66 in the blends were estimated based on the linear and non-linear Hoffman-Weeks (LHW and NLHW) extrapolative methods. The interaction mode between PVP and PA66 was investigated by FT-IR spectroscopy.

In this paper, the processing technologies of Nylon 6 POY (46dtex/72f) and DTY (38dtex/72f) fibers with super-denier by means of self-made rare-earth masterbatch are illustrated in details. The influence of rare-earth masterbatch’s content and knitting technologies on the properties of DTY fibers with porous superfine-denier is also particularly discussed. And finally we find out the best spinning techniques for PA 6 POY fiber and knitting process for PA 6 DTY fiber with porous superfine-denier.

The one-pot, organocatalytic Hayashi sequential reaction (HSR) of β-nitroacrylate, aldehyde, toluenethiol, and ethyl 2-(diethoxyphosphoryl)acrylate allowed the synthesis of almost stereoisomerically pure, highly functionalized polysubstituted cyclohexanes with very high diastereo- and enantio-selectivity (up to > 99 % ee). The one-pot synthesis consists of the tertiary amine modified diarylprolinol silyl ether-mediated asymmetric Michael reaction, a domino Michael reaction/Horner–Wadsworth–Emmons reaction, and a sulfa-Michael reaction. In addition, we have also demonstrated an improved protocol for the domino oxa-Michael/aldol reaction of salicyladehydes with α,β-unsaturated aldehydes with recyclable tertiary amine-modified diarylprolinol silyl ether 3d as an effective organocatalyst, which results in the formation of chiral chromenes with good enantioselectivities (up to 94 % ee). UV/Vis and CD spectroscopy provide a cross-validation method to elucidate the slight difference between electron-withdrawing 3d and diphenylprolinol silyl ether 3a, which can give indirect evidence for the enhancement of enantioselective induction with 3d in the above transformations.

Several sec-aromatic THP acetal compounds have been found to be suitable substrates for the [1,2]-Wittig rearrangement in the absence of an external electrophile, which resulted in the generation of new carbon-carbon bond and the facile synthesis of aromatic tertiary alcohols. More interestingly, an unexpected effect of chlorotrimethylsilane on this [1,2]-Wittig rearrangement of sec-aromatic THP acetal compounds was found, in which two different products involving oxidative procedure were obtained due to the competitive [1,4]-Sigmatropic rearrangement versus [1,2]-Wittig rearrangement

The wood-plastic composites (WPC) were prepared via compress molding by using the blends of high density polyethylene (HDPE) and modified polyethylene (MAPE) as the matrix and wood flour (WF) as filler. The effect of MAPE content in the matrix on the mechanical properties of the matrix and WPC was investigated. It was shown that the change of MAPE content in the matrix had no influence on the tensile strength of the matrix, but markedly reduced the impact strength of the matrix. Additionally, it had significant influence on the strength of WPC. When the content of wood flour and the content of the matrix remained fixed, with increasing the content of MAPE in the matrix, the tensile strength and the flexural strength of WPC tended to increase rapidly initially and then become steady. Moreover, with the increasing of MAPE concentration, the impact strength of WPC decreased when the low content of wood flour (30%) was filled, but increased at high wood flour loading (70%).

The structures and isomerization of magnesium fluorosilylenoid H2SiFMgF were investigated by ab initio molecular orbital theory. Four equilibrium structures and three isomeric transition states were located and fully optimized at the B3LYP/6-31G(d,p) and G3MP2B3 levels, respectively. Based on the B3LYP/6-31G(d,p) optimized geometries, harmonic frequencies of various structures were obtained and 29Si chemical shifts were calculated. The solvent effects were investigated by means of the polarizable continuum model using THF as a solvent at B3LYP/6-31G(d,p) level. Isomerization paths for isomers were confirmed by intrinsic reaction coordinate calculations. The calculated results show that tetrahedral structure has the lowest energy and is the most stable; tetrahedral, three-membered ring, and p-complex structures are suggested to be the experimentally detectable ones; and -complex structure has the highest energy and will not exist.

Using the low-valent titanium reagent (Zn/TiCl4), dichlorophenylsilane underwent a reductive polymerization reaction to give Si–H functional poly(phenylsilane) (Mw/Mn=2.5, Mn=2400) in a moderate yield. Applying this method, the corresponding organosilane copolymers (2b–2f) were also obtained. The absorption maxima of these organosilane copolymers are remarkably hypsochromically shifted in comparison with those of poly(diarylsilane)s.

A general catalytic conjugate addition with allyltrimethylsilane and chalcones is described. Allyltrimethylsilane undergoes the Sakurai–Michael reaction smoothly with high chemoselectivity in the presence of a catalytic amount of FeCl3/TMSCl under very mild and convenient conditions to afford the corresponding Michael adducts in high yields.

Indium(III) chloride is an effective Lewis acid catalyst for one-pot allylation–etherification and reductive etherification of aromatic aldehydes with functional silanes, allyltriethoxysilane, and triethoxysilane, at room temperature to afford corresponding ethers in excellent yields. Additionally, the InCl3-catalyzed reactions in the presence of TMSCl offer significant advantages in its ease of working-up for the preparation of unsymmetrical ethers under mild conditions.

We have investigated the use of Rh(PPh3)3Cl/ionic liquid (molten salt) as a thermoregulated and recyclable catalytic system for hydrosilylation. It was found that both conversion and selectivity could be influenced by the alkyl chains attached to the pyridinium and imidazolium cations. The Rh(PPh3)3Cl/ionic liquid (molten salt) catalyst system combines the advantages of an ionic liquid with convenient product separation, whilst the catalyst system can be reused at least 10 times without noticeable decrease of activity and selectivity.

Novel “greener” functionalized ionic liquids have been prepared by the reaction of 1,2‐epoxy propane and dilute sulfuric acid with [EMIm]Br or [BMIm]Br formed by alkyl bromide (RBr) and 1‐methylimidazole. This kind of ionic liquid could be possibly used as green solvent and catalyst, especially as phase‐transfer catalyst in organic chemistry (e.g., the synthesis of ethoxybenzene). Their chemical structures were characterized by 1H NMR, 13C NMR, and IR.

Atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) employing ethyl 2-bromoisobutyrate (EBiB)/CuBr as the initiating system was investigated at 50 °C in the absence of any additional ligand in the three room temperature ionic liquids (RTILs), 1-methyl-imidazolium acetate ([mim][CH 3 COO]), 1-methylimidazolium propionate ([mim][CH 3 CH 2 COO]) and 1-methylimidazolium butyrate ([mim][CH 3 CH 2 CH 2 COO]), respectively. All the polymerization in the three RTILs proceeded in a well-controlled manner. The sequence of the apparent polymerization rate constants was k app ([mim][CH 3 COO]) > k app ([mim][CH 3 CH 2 COO]) > k app ([mim][CH 3 CH 2 CH 2 COO]).

The lowest-energy structures of neutral and ionic Gen (n=11–19) clusters are obtained by using the full-potential linear-muffin-tin-orbital molecular-dynamics (FP-LMTO-MD) method based on some genetic operations. We find a number of new ground state structures, which are more stable than those reported previously. Most of the lowest energy structures for the neutral and ionic Gen (n=11–19) clusters are obviously different from those of the corresponding Sin clusters although the geometrical configurations of the small clusters (n

The structures and isomerization of magnesium chlorosilylenoid H 2 SiClMgCl were investigated by ab initio molecular orbital theory for the first time. Four equilibrium structures and three isomeric transition states were located and fully optimized at the G3MP2B3 level. For more accurate structural analysis, the B3LYP/cc-pVTZ and QCISD/6-311+G* calculations were performed, respectively. Based on the B3LYP/6-31G(d) optimized geometries, 29 Si chemical shifts and harmonic frequencies of various structures were obtained. Isomerization paths for isomers were confirmed by the intrinsic reaction coordinate (IRC) calculations. Tetrahedral, three-membered ring and p-complex structures are suggested to be experimentally detectable ones. σ-Complex structure has the highest energy and will not exist. The solvent effects were considered by means of the polarizable continuum model (PCM) using THF as a solvent.

A series of aryl ether oligomers end-capped with ethynyl groups have been synthesised via a three-step process, i.e. iodination of oligo-aryl ethers, nucleophilic substitution of the iodide group with 2-methyl-3-butyn-2-ol catalysed by Pd/Cu and subsequent deacetonation in KOH/toluene. Effects of reaction temperature and the Pd/Cu catalyst on iodination and the substitution reaction are discussed.

In the title compound, [Mn(C4H2O4)(C7H6N2)3]n, maleate dianions bridge neighbouring MnII ions to form helical polymeric chains. The Mn ion assumes a distorted octa­hedral coordination geometry, formed by two maleate and three benzimidazole ligands. One maleate carboxyl group chelates to the Mn atom with longer Mn—O bond distances while the other carboxyl group coordinates in a monodentate manner to the Mn atom.

The synthetic use of tertiary amines for the esterification of equimolar amounts of carboxylic acids involves an sp3 C—N bond cleavage.

Use of the environmentally benign amino-functionalized polysiloxanes (PAP or CAP) as organocatalyst allows for the title reactions to proceed under relatively mild reaction conditions.

A combined prolinol silyl ether—o-nitrobenzoic acid organocatalyst is successfully applied in the one-pot reaction of aldehydes (I) with β-nitroacrylate (II), phosphoryl acrylate (III) and toluenethiol (IV) to give highly functionalized cyclohexane derivatives (V) in high to excellent stereoselectivities (up to < 98% d.e.

In the present investigation, 24 cases of meningoima tissues (including 12 cases of benign tumor and 12 cases of malignant tumor 12) were detected using FT-mid-IR spectroscopy linked with attenuated total reflectance (ATR) accessory. These FTIR spectra obtained from the above-mentioned meningoima tissues were analyzed and compared. Significant differences were found in the spectral features of different kinds of meningoima tissues for example fibrous type meningoima and endothelioid meningoima; and for the same type of meningoima tissues the significant differences in the spectram features can be also observed with the increase of grade malignancy. The malignant tumor can be distinguished primarily from benign tumor by the changes of position, shape and intensity of infrared absorption bands, particularly in the ranges of 1 000-1 500 cm(-1). The results show that the peak position of the bands (such as 1 160 cm(-1)) can be used to distinguish the characteristic of meningoima which are in agreement with the pathological results. The accuracy is larger than 85%. These results demonstrate that FT-mid-IR spectroscopy exhibits prospect to develop a novel, non-invasive and rapid method for the diagnosis the brain tumors.

A general catalytic conjugate addition with allyltrimethylsilane and chalcones is described. Allyltrimethylsilane undergoes the Sakurai–Michael reaction smoothly with high chemoselectivity in the presence of a catalytic amount of FeCl3/TMSCl under very mild and convenient conditions to afford the corresponding Michael adducts in high yields.

Indium(III) chloride is an effective Lewis acid catalyst for one-pot allylation–etherification and reductive etherification of aromatic aldehydes with functional silanes, allyltriethoxysilane, and triethoxysilane, at room temperature to afford corresponding ethers in excellent yields. Additionally, the InCl3-catalyzed reactions in the presence of TMSCl offer significant advantages in its ease of working-up for the preparation of unsymmetrical ethers under mild conditions.

Novel “greener” functionalized ionic liquids have been prepared by the reaction of 1,2‐epoxy propane and dilute sulfuric acid with [EMIm]Br or [BMIm]Br formed by alkyl bromide (RBr) and 1‐methylimidazole. This kind of ionic liquid could be possibly used as green solvent and catalyst, especially as phase‐transfer catalyst in organic chemistry (e.g., the synthesis of ethoxybenzene). Their chemical structures were characterized by 1H NMR, 13C NMR, and IR.

m-lodophenol (4a) was found to couple with 2-methylbut-3-yn-2-ol (5) in the presence of PdCl 2 -Cul-Ph 3 P-in triethylamine to afford 3-(3-hydroxy-3-methylbut-1-ynyl)phenol(6a), which was conveniently converted into m-ethynylphenol (7a). Under the same conditions, p-iodophenol did not couple with 5. However, p-iodo-1-[(tetrahydro-2H-pyran-2-yl)oxy]benzene (4b) did react with 5 to afford 1-[(tetrahydro-2H-pyran-2-yl)oxy]-4-[2-hydroxy-2-methyl-4-but-3-ynyl]benzene (6b), which was similarly converted into 1-[(tetrahydro-2H-pyran-2-yl)oxy]-4-ethynylbenzene (7b) with loss of acetone. Removal of the tetrahydropyranyl protecting group from 7b furnished p-ethynylphenol (8).

Interface design plays a crucial role in developing superior mechanical performance of graphene/polymer nanocomposites. Herein, we report a facile approach to the fabrication of advanced polymeric nanocomposites of epoxy by the incorporation of polyetheramine-functionalized graphene oxide (PEA-f-GO). Two types of PEA molecules with different molecular lengths were used to synthesize the PEA-f-GO sheets. The chemical bonds formed between the amine functional groups on the GO surface and the epoxy resin during curing provided strong sheet/matrix interfacial adhesion. The addition of PEA-f-GO was found to produce significant enhancements in the mechanical properties of epoxy, including elastic modulus, tensile strength, elongation at break and toughness. In particular, the PEA-f-GO sheets containing shorter PEA molecules produced higher improvement in strength but smaller increases in both ductility and toughness than those containing longer PEA molecules. For example, at 0.50 wt% filler loading, two nanocomposites showed increases of 63% and 51% in tensile strength and 90% and 119% in toughness as compared to the unfilled epoxy. Our results suggest that the interphases between the GO and the polymer matrix can be tuned by varying the molecular lengths of grafted modifiers, thereby providing a new route for the rational designing and development of the GO-based composite materials.

The title MnII complex, [Mn(C7H5O3)2(C10H8N2)2], has twofold symmetry, with the MnII atom located on a twofold axis. Two 4-hydroxybenzoate anions and two 2,2′-bipyridine coordinate to the MnII atom which has a distorted octahedral geometry. Hydrogen bonding between the carboxylate and hydroxyl groups forms a sheet perpendicular to the a axis.

We investigate the electronic states of IC60BA and PC71BM using first-principles calculations and photoelectron spectroscopy (PES) measurements. The energy level structures for all possible isomers are reported and compared with those of C60, C70 and PC61BM. The attachment of the side chains can raise the LUMO energies and decrease the HOMO-LUMO gaps, and thus helps to increase the power-conversion efficiency of bulk heterojunction solar cells. In the PES studies, we prepared IC60BA and PC71BM films on Si:H(111) substrates to construct adsorbate/substrate interfaces describable with the integer charge-transfer (ICT) model. Successful measurements then revealed that one of the most important material properties for an electron acceptor, the energy of the negative integer charge-transfer state (EICT−), is 4.31 eV below the vacuum level for PC71BM. The EICT− of IC60BA is smaller than 4.14 eV.

In this article, for the first time, we describe that commercially available and environmentally benign amine-functional polysiloxanes (AFPs) could be used as highly efficient metal-free amino catalysts in multicomponent Gewald reactions, α-allylic alkylations of aldehydes, and Knoevenagel condensations. Using catalytic amounts of AFPs, these transformations, including the Gewald reactions of ketones, sulfur, and ethyl 2-cyanoacetate, α-allylic alkylations of aldehydes and Knoevenagel condensations of aldehydes and the methylene-activated substrates may be carried out under mild conditions to give corresponding products in good yields.