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Synthesis of valuable chemicals from lignin based compounds is critical for the application of biomass. Here, we develop a method of preparing aryl acetates by the carbonylation of aryl methyl ethers or phenols under low CO pressure. Good to excellent yields of aryl acetates were obtained using different substrates, and a possible reaction mechanism was proposed by conducting a series of control experiments. This method may provide a potential way for the utilization of lignin.

The catalytic transformation of aryl esters to hydroxyacetophenones via Fries rearrangement over solid acids is of interest to avoid the use of corrosive and toxic Lewis and Br?nsted acids traditionally applied. Microporous zeolites are known to catalyze the reaction of simple substrates such as phenyl acetate, but their application to substituted derivatives has received limited attention. To refine structure-activity relationships, here we examine the impact of various parameters including the solvent polarity, water content, acidic properties, and framework type on the reaction scheme in the Fries rearrangement of p-tolyl acetate over common solid acids. The results confirm the importance of providing a high concentration of accessible Br?nsted acid sites, with beta zeolites exhibiting the best performance. Extension of the substrate scope by substituting methyl groups in multiple positions identifies a framework-dependent effect on the rearrangement chemistry and highlights the potential for the transformation of dimethylphenyl acetates. Kinetic studies show that the major competitive path of cleavage of the ester C-O bond usually occurs in parallel to the Fries rearrangement. The possibility of sequentially acylating the resulting phenol depends on the substrate and reaction conditions.

Alzheimer's disease (AD) is a neurodegenerative disorder with no radical therapy. Aggregation of amyloid β-peptide (Aβ) induced by various factors is associated with pathogenesis of AD. A pyridine amine derivative, 3-bis(pyridin-2-ylmethyl)aminomethyl-5-h

An approach has been developed for the copper-catalyzed acetylation of phenols and anilines with potassium thioacetate as an acetylating reagent. Although only electron-rich phenols and anilines are compatible with this protocol, the reaction can provide moderate to high yields under mild conditions. Compared with other acetylating reagents, the current reagent has certain advantages, such as its low cost, easy availability, stability, insensitivity to water or air, and ease of storage.

PF-543 is a non-sphingosine analogue with inhibitory effect against SK1, based on a Ki of 4.3 nM and 130-fold selectivity for SK1 over SK2. Since the development of PF-543, animal studies demonstrated its valuable role in multiple sclerosis, myocardial in

The five reported structural isomorphic porous coordination polymers (PCPs) 1-5, namely, [Zn(L)(ip) (1), Zn(L)(aip) (2), Zn(L)(hip) (3), Zn(L)(nip) (4), and Zn(L)(HBTC) (5) (L = N4,N4′-di(pyridine-4-yl)biphenyl-4,4′-dicarboxamide, H2ip = isophthalic acid, H2aip = 5-aminoisophthalic acid, H2hip = 5-hydroxyisophthalic acid, H2nip = 5-nitroisophthalic acid, H3BTC = 1,3,5-benzenetricarboxylic acid)] were used to catalyze the acetylation of phenol. All these heterogeneous catalysts exhibit good catalytic efficiency and size-selectivity toward the acetylation of phenols owing to their unsaturated metal centers, non-coordinated amide, and suitable channel size and shape. Among them, 2 displays the highest catalytic activity and excellent cooperative catalysis due to the presence of basic non-coordinated amide groups.

The invention provides a preparation method of 3,5-dimethylphenol. The method comprises the following steps: xylene (one or a mixture of o-xylene, m-xylene and p-xylene) and alkyl halide or anhydride are subjected to a reaction under the effect of a catalyst, and an intermediate 3,5-dimethylcarbonyl compound is produced under a certain condition; the intermediate is oxidized under the effect of a peroxide, such that 3,5-dimethylphenol ester is produced; and 3,5-dimethylphenol ester is hydrolyzed, such that 3,5-dimethylphenol is obtained. According to the method, xylene is adopted as an initial raw material, and is processed through the tree steps of carbonylation, oxidation and hydrolysis, such that a target product can be prepared with high yield. Therefore, an assumption of synthesizing 3,5-dimethylphenol with high yield under a mild condition is made possible. Compared to prior arts, the method provided by the invention has the advantages of low raw material cost, less three-waste, and mild reaction condition. The method is especially suitable for large-scale productions.

Porous coordination polymers (CPs) with partially uncoordinated pyridyl rings based on rationally designed polypyridyl linkers are appealing from the point of view of their application as nucleophilic catalysts. A D2d--symmetric tetradentate organic linker L, that is, 2,2 ',6,6'-tetramethoxy-3,3',5,5'-tetrakis(4-pyridyl)biphenyl, was designed and synthesized for metal-assisted self-assembly aimed at porous CPs. Depending on the nature of the metal ion and the counter anion, the ligand L is found to function as a 3- or 4-connecting building block leading to porous CPs of diverse topologies. The reaction of L with Zn(NO3)2 and Cd(NO3)2 yields porous 2D CPs of "fes" topology, in which the tetrapyridyl linker L serves as a 3-connecting unit with its free pyridyl rings well exposed into the pores. The functional utility of these porous CPs containing uncoordinated pyridyl rings is demonstrated by employing them as efficient heterogeneous nucleophilic catalysts for acetylation of a number of phenols with varying electronic properties and reactivities.

An efficient annulation strategy involving the reaction of phenolic acetates with acrylates in the presence of [Rh2(OAc)4] as catalyst and formic acid as reducing agent, leading to the high yield synthesis of coumarin derivatives, has been developed. The addition of NaOAc as a base increased the yield of the products. The reaction is quite successful for both electron-rich as well as electron-deficient phenolic acetates, affording coumarins with excellent regioselectivity, and proceeds via C-H bond activation proven by deuterium incorporation studies.

Sphingosine kinases (SphK1, SphK2) are main regulators of sphingosine-1-phosphate (S1P), which is a pleiotropic lipid mediator involved in numerous physiological and pathophysiological functions. SphKs are targets for novel anti-cancer and anti-inflammatory agents that can promote cell apoptosis and modulate autoimmune diseases. Herein, we describe the design, synthesis and evaluation of an aminothiazole class of SphK inhibitors. Potent inhibitors have been discovered through a series of modifications using the known SKI-II scaffold to define structure-activity relationships. We identified N-(4-methylthiazol-2-yl)-(2,4′-bithiazol)-2′-amine (24, ST-1803; IC50values: 7.3 μM (SphK1), 6.5 μM (SphK2)) as a promising candidate for further in vivo investigations and structural development.

A silver trifluoromethanesulfonate (AgOTf)-promoted direct and mild formylation of benzenes has been developed. The reaction utilizing dichloromethyl methyl ether (Cl2CHOMe) and AgOTf powerfully formylated various substituted benzenes under temperature conditions as low as -78 C without losing the protecting groups on the phenolic hydroxyl group.

Rapid and practical green acetylation and tetrahydropyranylation routes of structurally diverse alcohols and phenols were applied under solvent-free reaction conditions providing excellent yields, using catalytic amounts of environmentally friendly sulfonated ordered nanoporous carbon (CMK-5-SO 3H). Non-toxic nature of the catalyst, its easy handling, recovery and reusability, and the absence of any solvent characterize the presented procedures as efficient methods. These procedures provide methods for the separation of the product by simple filtration.

The catalytic activity of highly thermal stable, hydrophobic, and complete heterogeneous propylsulfonic acid functionalized nanostructured SBA-15 for excellent acetylation of alcohols and phenols with acetic anhydride at ambient temperature in solvent-free conditions was examined under environmentally benign reaction conditions. The salient features of this protocol are the absence of solvent, a green experimental procedure, and simple reusability of the catalyst (at least five reaction cycles).

Iron-doped single-walled carbon nanotubes (Fe/SWCNTs) represent an efficient and new heterogeneous reusable catalyst for the acylation of a variety of alcohols, phenols, carboxylic acids and amines with acid chlorides or acid anhydrides under solvent-free conditions. The reactions of various primary, secondary, tertiary, and benzylic alcohols, diols, phenols, as well as aromatic and aliphatic amines give acylated adducts in good to excellent yields.

A clean bifurcation between two important photochemical reactions through competition of a triplet state Type II H-abstraction reaction with a photo-Favorskii rearrangement for (o/p)-hydroxy-o-methylphenacyl esters that depends on the water content of the solvent has been established. The switch from the anhydrous Type II pathway that yields indanones to the aqueous-dependent pathway producing benzofuranones occurs abruptly at low water concentrations (～8%). The surprisingly clean yields suggest that such reactions are synthetically promising.

A new and efficient dynamic kinetic resolution (DKR) process of secondary aromatic alcohols was developed with acid resins as racemization catalysts. Acid resin CD8604 was shown to have excellent racemization activity and good biocompatibility. When employing CD8604 and complex acyl donors as racemization catalyst and acyl donor, respectively, enantiomerically pure aromatic acetate was obtained with excellent yield and ee values through the DKR process. It is noteworthy that the system could be reused more than 10 times with little loss of yield and ee value.

The present invention provides a compound represented by the formula (I): [wherein R is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, p is 0, 1 or 2, and when p is 2, each R may be the same or different, R1 is a hydrogen atom or an optionally substituted hydrocarbon group, R2 is an optionally substituted aromatic group, Ring A is an optionally substituted monocyclic aromatic ring or optionally substituted bicyclic aromatic fused ring, X1 is an oxygen atom or a sulfur atom, X2 is a bond, an oxygen atom or -S(O)n- (wherein n is 0, 1 or 2), Y is a bond, an oxygen atom, -S(O)m-, -C(=O)-N(R3)- or -N(R3)-C(=O)- (R3 is a hydrogen atom, an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, and m is 0, 1 or 2), M1, M2 and M3 may be the same or different and are each independently a bond or an optionally substituted divalent aliphatic hydrocarbon group, and M4 is an optionally substituted divalent aliphatic hydrocarbon group] or a salt thereof, which is useful as a prophylactic and/or therapeutic agent for lipid metabolism abnormality, arteriosclerotic disease and sequelae thereof, diabetes mellitus and the like.

The dicopper(II) complex [Cu2(L)]4+ (L =α,α′-bis{bis[2-(1′-methyl-2′- benzimidazolyl)ethyl]amino}-m-xylene) reacts with hydrogen peroxide to give the dicopper(II) -hydroquinone complex in which the xylyl ring of the ligand has undergone a double hydroxylation reaction at ring positions 2 and 5. The dihydroxylated ligand 2,6-bis({bis[2-(3-methyl-1 H-benzimidazo[-2-yl)ethyl]amino}methyl)benzene-1,4-diol was isolated by decomposition of the product complex. The incorporation of two oxygen atoms from H2O2 into the ligand was confirmed by isotope labeling studies using H218O2. The pathway of the unusual double hydroxylation was investigated by preparing the two isomeric phenolic derivatives of L, namely 3,5-bis({bis[2-(1-methyl- 1H-benzimidazol-2-yl)ethyl]amino}methyl) phenol (6) and 2,6-bis({bis[2-(1-methyl-1H-benzimidazol-2-yl)- ethyl]amino}methyl)phenol (7), carrying the hydroxyl group in one of the two positions where L is hydroxylated. The dicopper(II) complexes prepared with the new ligands 6 and 7 and containing bridging μ-phenoxo moieties are inactive in the hydroxylation. Though, the dicopper(II) complex 3 derived from 6 and containing a protonated phenol is rapidly hydroxylated by H202 and represents the first product formed in the hydroxylation of [Cu2(L)]4+. Kinetic studies performed on the reactions of [Cu2(L)]4+ and 3 with H2O2 show that the second hydroxylation is faster than the first one at room temperature (0.13 ± 0.05 s-1 vs 5.0(±0.1) X 10-3 s-1) and both are intramolecular processes. However, the two reactions exhibit different activation parameters (ΔH? = 39.1 ± 0.9 kJ mol-1 and ΔS? = -115.7 ± 2.4 J K-1 mol-1 for the first hydroxylation; ΔH? = 77.8 ± 1.6 kJ mol-1 and ΔS? = -14.0 ± 0.4 J K-1 mol-1 for the second hydroxylation). By studying the reaction between [Cu2(L)]4+. and H2O2 at low temperature, we were able to characterize the intermediate η1:η1-hydroperoxodicopper(II) adduct active in the first hydroxylation step, [Cu2(L)(OOH)]3+ [λmax = 342 (ε 12 000), 444 (ε 1200), and 610 nm (ε 800 M-1cm-1); broad EPR signal in frozen solution indicative of magnetically coupled Cu(II) centers].

The use of titanium(IV) chloride as a Lewis acid for direct ortho-acylation of phenols and naphthols proves to be a convenient, more general and direct route to various hydroxyaryl ketones. The route is regioselective, leading to ortho C-acylated products in satisfactory to high yields in most cases.

Several substituted 2'-hydroxy-4',6-dimethylchalcones undergo a solid state intramolecular Michael-type addition reaction to yield the corresponding flavanones, at temperatures significantly below the melting points of the reactants or products.Single crystal X-ray diffraction studies of the reactant and product phases have beeen carried out and indicate that these solid state reactions most likely proceed in a non-topochemical fashion.A similar conclusion is deduced from X-ray powder diffraction, differential scanning calorimetry and packing energy calculations.Reaction in the defect regions is probably important because considerable relaxation in the molecular conformation of the chalcone is required in the crystal before intramolecular ring-closure to the flavanone can occur.

Phenyl acetates were selectively obtained in good yields by cyclocarbonylation of 2,4-pentadienyl acetates in the presence of NEt3, Ac2O, and a catalytic amount of palladium complexes such as PdCl2(PPh3)2 at 120-140 deg C under 50 atm of CO.No five-membered ring products were observed.A platinum complex PtCl2(PPh3)2 was also effective as a catalyst.The reaction of 5-phenyl-2,4-pentadienyl bromide with M(CO)(PPh3)3 (M = Pd or Pt) under CO gave the corresponding 6-phenyl-3,5-hexadienoyl complexes in a high yield, which in turn afforded 2-acetoxybiphenyl in 41-51percent yield on heating to 160 deg C under 50 atm of CO in the presence of NEt3 and Ac2O.Similar 3,5-hexadienoyl complexes are proposed to be intermediates in the catalytic cyclocarbonylation of 2,4-pentadienyl acetates.On the other hand, PdCl2(PPh3)2-catalyzed carbonylation of o-(bromomethyl)(1-alkenyl)benzenes in the presence of NEt3 and Ac2O gave 2-naphthyl acetates in moderate yields, while the reaction in the absence of Ac2O gave five-membered ring products such as 2-indanones or a tricyclic lactone by incorporation of one or two CO, respectively.

p-Hydroxy phenone derivatives of the general formula I STR1 where R 1, R 2 and R 3 are identical or different and are methyl, chlorine, bromine and hydrogen, but R 1, R 2 and R 3 are not all H,R 4 and R 5 are identical or different and are H, C 1-C 4-alkyl, or OR 6, but R 4 and R 5 are not both H,X is a--CH=CH--,--CH. sub.2 CH 2 or--CH. sub.2--bridge,Y is a straight-chain or branched, saturated or unsaturated C 1-C 4 bridge, and Z is NR 6 R 7, where R 6 and R 7 are, independently of one another, hydrogen or C 1-4-alkyl, or Z is a 5-or 6-membered ring with a nitrogen atom in the 1 position and, where appropriate, additionally a second N atom or an O or S atom, the second N atom being substituted by R 7, as well as the physiologically tolerated salts thereof,are used to prepare drugs antiarrhythmic of Vaughan-Williams class III.

The scope and limitation of novel palladium-and platinum-catalyzed cyclocarbonylation reactions of 3-arylallyl and 2,4-pentadienyl acetates are described.The detailed mechanism of these reactions is also discussed.

Palladium-catalysed cyclocarbonylation of penta-2,4-dienyl acetates in the presence of NEt3 and Ac2O selectively gives phenyl acetates in good yields.

A simple and general benzocyclization sequence, useful in the conversion of α-methylene ketones/aldehydes 1a-f to phenolic acetates 6a-g via the dienoic acids 5a-g is presented.The technique has provided a new route to the terpenoids, thymol acetate (6f) and (R)-(-)-curcuphenol acetate (6g).