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Observed variations in the δ13C and δ15N content of amphetamines are shown to be attributable to kinetic isotope effects during synthesis; chemical degradation and isotopic characterisation provides a means to identify the synthetic origins of illicit MDMA and other amphetamines.

The Wacker-Tsuji aerobic oxidation of various allyl(hetero)arenes under photocatalytic conditions to form the corresponding methyl ketones is presented. By using a palladium complex [PdCl2(MeCN)2] and the photosensitizer [Acr-Mes]ClO4 in aqueous medium and at room temperature, and by simple irradiation with blue led light, the desired carbonyl compounds were synthesized with high conversions (>80%) and excellent selectivities (>90%). The key process was the transient formation of Pd nanoparticles that can activate oxygen, thus recycling the Pd(II) species necessary in the Wacker oxidative reaction. While light irradiation was strictly mandatory, the addition of the photocatalyst improved the reaction selectivity, due to the formation of the starting allyl(hetero)arene from some of the obtained by-products, thus entering back in the Wacker-Tsuji catalytic cycle. Once optimized, the oxidation reaction was combined in a one-pot two-step sequential protocol with an enzymatic transformation. Depending on the biocatalyst employed, i. e. an amine transaminase or an alcohol dehydrogenase, the corresponding (R)- and (S)-1-arylpropan-2-amines or 1-arylpropan-2-ols, respectively, could be synthesized in most cases with high yields (>70%) and in enantiopure form. Finally, an application of this photo-metal-biocatalytic strategy has been demonstrated in order to get access in a straightforward manner to selegiline, an anti-Parkinson drug. (Figure presented.).

A widely applicable approach was developed to synthesize ketones, esters, amides via the oxidative C?C bond cleavage of readily available alkyl aldehydes. Green and abundant molecular oxygen (O2) was used as the oxidant, and base metals (cobalt and copper) were used as the catalysts. This strategy can be extended to the one-pot synthesis of ketones from primary alcohols and α-ketoamides from aldehydes.

The monoarylation of acetone is a powerful transformation, but is typically performed at temperatures significantly in excess of its boiling point. Conditions described for performing the reaction at ambient temperatures led to significant dehalogenation when applied to a complex aryl halide. We describe our attempts to overcome both issues in the context of our drug-discovery program.

The challenging nickel-catalyzed mono-α-arylation of acetone with aryl chlorides, pivalates, and carbamates has been achieved for the first time. A nickel/Josiphos-based catalytic system is shown to feature unique catalytic behavior, allowing the highly selective formation of the desired mono-α-arylated acetone. The developed methodology was applied to a variety of (hetero)aryl chlorides including biologically relevant derivatives. The methodology has been extended to the unprecedented coupling of acetone with phenol derivatives. Mechanistic studies allowed the isolation and characterization of key Ni0 and NiII catalytic intermediates. The Josiphos ligand is shown to play a key role in the stabilization of NiII intermediates to allow a Ni0/NiII catalytic pathway. Mechanistic understanding was then leveraged to improve the protocol using an air-stable NiII pre-catalyst.

Herein, a sequential and selective chemoenzymatic approach is described involving the metal-catalysed Wacker-Tsuji oxidation of allylbenzenes followed by the amine transaminase-catalysed biotransamination of the resulting 1-arylpropan-2-ones. Thus, a series of nine optically active 1-arylpropan-2-amines were obtained with good to very high conversions (74–92%) and excellent selectivities (>99% enantiomeric excess) in aqueous medium. The Wacker-Tsuji reaction has been exhaustively optimised searching for compatible conditions with the biotransamination experiments, using palladium(II) complexes as catalysts and iron(III) salts as terminal oxidants in aqueous media. The compatibility of palladium/iron systems for the chemical oxidation with commercially available and made in house amine transaminases was analysed, finding ideal conditions for the development of a general and stereoselective cascade sequence. Depending on the selectivity displayed by selected amine transaminase, it was possible to produce both 1-arylpropan-2-amines enantiomers under mild reaction conditions, compounds that present therapeutic properties or can be employed as synthetic intermediates of chiral drugs from the amphetamine family. (Figure presented.).

The invention is suitable for the technical fields of organic compounds and synthesis, and provides a carbazolyl phosphorus ligand as well as a preparation method and application thereof. The carbazolyl phosphorus ligand is one of a compound 1, a compound 2 and a compound 3 with structures shown by a formula 1, a formula 2 and a formula 3 (shown in the description) respectively, wherein R1 is phenyl or alkyl, R2, R3, R4, R5, R6, R7, R8 and R9 independently are one of hydrogen, C5-C10 alkyl, methoxyl, oxymethyl, ethyoxyl, phenyl, fluorine group, and pyridyl; and R2, R3, R4, and R5 cannot be hydrogen at the same time.

A mild, efficient protocol for oxidative cleavage of C-C bonds in aldehydes has been developed that employs alkali metal hydrides as reagents and oxygen from air as a terminal oxidant. The method is applicable to a broad substrate range.

We report a newly developed carbazoyl-derived P,N-type phosphine ligand (L1) for the monoarylation of acetone with aryl chlorides. The proposed Pd(dba)2/L1 catalyst exhibited remarkable catalytic reactivity toward highly electron rich and sterically congested aryl chlorides, with catalyst loading as low as 0.1 mol % of Pd along with excellent chemoselectivity. A reaction rate study of the system using electronically diverse aryl chlorides determined the mechanisms regarding the rate-limiting steps in this reaction. The oxidative addition adduct of Pd-PhenCar-Phos with p-chlorotoluene showed the participation of N-Pd coordination in the metal complex. The isolated palladium complex C1 could be utilized as a precatalyst in the transformation and achieved performance comparable to that of the in situ generated palladium species.

A formal total synthesis of (-)-talampanel (1), a 2,3-benzodiazepine is described. This work was undertaken to utilize greener reaction conditions. Safrole (a renewable source) was converted to (1) in eight steps, including an enantioselective bioreduction using carrots as the key step. Microwave irradiation was also used to perform three reaction steps.

The rational design of a phosphine ligand for the reductive elimination-demanding Pd-catalyzed mono-α-arylation of acetone is demonstrated and reported. The catalyst is tolerant of previously proven challenging electron-deficient aryl chlorides and provides excellent product yields with down to 0.1 mol % Pd. Preliminary investigations suggest that the rate-limiting step for the proposed system is the oxidative addition of aryl chlorides, in which it contradicts previous findings regarding the α-arylation of acetone with aryl halides.

The first examples of acetone mono-α-arylation at room temperature are described, enabled by use of a [Pd(cinnamyl)Cl]2/JosiPhos catalyst system. (Hetero)aryl chloride, bromide, and iodide electrophiles featuring or lacking ortho-substitution, and comprising a range of functionalities (e.g., alkoxy, cyano, fluoro, trifluoromethyl, or alkenyl) and heteroaryl motifs (e.g., pyrrole, pyridine, isoquinoline, quinoline, quinaldine, (benzo)thiophene, benzothiazole, or benzodioxole) were successfully accommodated. Proof-of-principle experiments confirm that other (hetero)aryl methyl ketones can also be employed in such room temperature mono-α-arylations. The established substrate scope is the most extensive reported to date for acetone mono-α-arylation under any conditions, and more generally represents the first room temperature ketone mono-α-arylations employing a structurally diverse set of (hetero)aryl chlorides. Chill out: The first examples of acetone mono-α-arylation at room temperature are described. The substrate scope is the most extensive reported to date for acetone mono-α-arylation under any conditions, and represents the first room temperature ketone mono-α-arylations employing a diverse set of (hetero)aryl chlorides.

A two-step synthesis of various enantiomerically pure 1-aryl-3- methylisochroman derivatives was accomplished through asymmetric biocatalytic ketone reduction followed by an oxa-Pictet-Spengler reaction. The compounds were obtained in good to excellent yield (47-92 %) in favor of the syn diastereomers [dr (syn/anti) up to 99:1]. Enantiopure arylpropanols serving as pronucleophiles for the C-C bond-formation step were obtained by biocatalytic reduction by employing enantiocomplementary alcohol dehydrogenases, which gave access to the (S) and (R) enantiomer with up to >99 % conversion and up to >99 % ee. A two-step sequence involving a biocatalytic hydrogen-transfer reduction and a syn-diastereoselective oxa-Pictet-Spengler reaction was established to provide a series of 1-aryl-3-methylchroman derivatives with perfect enantioselectivity; PTSA = para-toluenesulfonic acid. Copyright

Mor(DalPhos) for Me(sylates): Described are the first examples of ketone mono-α-arylation and primary aliphatic amine monoarylation employing aryl methanesulfonate coupling partners. A range of functionalized aryl mesylates were employed with dialkyl ketones, and also with primary and secondary amines as well as the otherwise challenging coupling partners acetone and methylamine. Ad=adamantyl. Copyright

Set the ace(tone): A palladium catalyst derived from the bidentate XantPhos ligand and Pd(OAc)2 has enabled broadly applicable mono-α-arylations of acetone to be performed with air- and moisture-stable aryl imidazolylsulfonates as most user-friendly electrophiles (see scheme). Copyright

We report the first example of selective Pd-catalyzed mono-α- arylation of acetone employing aryl chlorides, bromides, iodides, and tosylates. The use of appropriately designed P,N-ligands proved to be the key to controlling the reactivity and selectivity. The reaction affords good yields with substrates containing a range of functional groups at modest Pd loadings using Cs2CO3 as the base and employing acetone as both a reagent and the solvent.(Figure Presented)

A palladium-catalyzed, aerobic oxidation of naturally occurring allylbenzenes, i.e., eugenol, methyleugenol, safrole, and estragole, in dimethylacetamide/water solutions under mild conditions has been developed, in which palladium(II) chloride is used in the absence of co-catalysts or special stabilizing ligands as the sole and recyclable catalyst. Methyl ketones that are important for the flavour and pharmaceutical industries have been obtained in good to excellent yields with low catalyst loadings (1-2 mol%) and high average turnover frequencies. This simple catalytic method represents an ecologically benign and economically attractive route to industrially valuable compounds starting from renewable substrates easily available from essential oils.

Drug profiling, or the ability to link batches of illicit drugs to a common source or synthetic route, has long been a goal of law enforcement agencies. Research in the past decade has explored drug profiling with isotope ratio mass spectrometry (IRMS). This type of research can be limited by the use of substances seized by police, of which the provenance is unknown. Fortunately, however, some studies in recent years have been carried out on drugs synthesized in-house and therefore of known history. In this study, 18 MDMA samples were synthesized in-house from aliquots of the same precursor by three common reductive animation routes and analyzed for 13C, 15N, and 2H isotope abundance using IRMS. For these three preparative methods, results indicate that 2H isotope abundance data is necessary for discrimination by synthetic route. Furthermore, hierarchical cluster analysis using 2H data on its own or combined with 13C and/or 15N provides a statistical means for accurate discrimination by synthetic route.

A facile synthesis of aryl propanones using aromatic amines as precursors, via an improved Meerwein arylation reaction under mild conditions, is reported. Copyright Taylor & Francis Group, LLC.

Fe-HCl mixture was found to selectively perform oxidative hydrolysis of the nitroalkenes 1a-j and nitroalkanes 2a-j to the ketones 3a-j. Also, the reagent was observed to deprotect the oximes 7a-j to carbonyl compounds 8a-j in excellent yields.

Ecstasy samples often contain byproducts of the illegal, uncontrolled synthesis of N-methyl-3,4-methylenedioxy-amphetamine or 3,4-methylenedioxy- methamphetamine (MDMA). MDMA and eight chemically defined byproducts of MDMA synthesis were investigated for their interaction with the primary sites of action of MDMA, namely the human plasmalemmal monamine transporters for norepinephrine, serotonin, and dopamine [(norepinephrine transporter (NET), serotonin transporter (SERT), and dopamine transporter (DAT)]. SKN-MC neuroblastoma and human embryonic kidney cells stably transfected with the transporter cDNA were used for uptake and release experiments. Two of the eight compounds, 1,3-bis (3,4-methylenedioxyphenyl)-2-propanamine (12) and N-formyl-1,3-bis (3,4-methylenedioxyphenyl)-prop-2-yl-amine (13) had uptake inhibitory potencies with IC50 values in the low micromolar range similar to MDMA. Compounds with nitro instead of amino groups and a phenylethenyl instead of a phenylethyl structure or a formamide or acetamide modification had IC50 values beyond 100 μM. MDMA, 12, and 13 were examined for induction of carrier-mediated release by superfusion of transporter expressing cells preloaded with the metabolically inert transporter substrate [3H]1-methyl-4-phenylpyridinium. MDMA induced release mediated by NET, SERT, or DAT with EC50 values of 0.64, 1.12, and 3.24 μM, respectively. 12 weakly released from NET- and SERT-expressing cells with maximum effects less than one-tenth of that of MDMA and did not release from DAT cells. 13 had no releasing activity. 12 and 13 inhibited release induced by MDMA, and the concentration dependence of this effect correlated with their uptake inhibitory potency at the various transporters. These results do not support a neurotoxic potential of the examined ecstasy synthesis byproducts and provide interesting structure-activity relationships on the transporters. Copyright

The present invention provides a system for the improved detection of ecstasy-class compounds in biological samples. New ecstasy-class analogs are provided for detection of such ecstasy-class drugs. These analogs are compounds, or salts thereof, of a 2-amino-methylenedioxyphenyl (MDP) derivative attached to Z, where Z is a moiety capable of bonding, either directly or indirectly, with an immunogenic carrier, a detectable label, or a solid capture vehicle. Such analogs may be used to construct immunogens, enzyme or enzyme-donor conjugates, and other conjugates. The immunogens reproducibly generate antibodies with an exquisite ability to distinguish various ecstasy-class drugs in biological samples from potentially interfering substances. The specific antibodies and the conjugates may be used to distinguish and measure various ecstasy-class compounds in biological samples, such as those obtained from an individual suspected of substance abuse. In another aspect, the invention includes certain reagents, reagent combinations, and kits for performing assay methods for ecstasy-class compounds in a biological sample.

The synthesis of 1-(4-aminophenyl)-4-methyl-7,8-methylene-dioxy-5H-2,3-benzodiazepine (GYKI 52466, 1), the prototype of a series of noncompetitive AMPA receptor antagonists, and its 3,4-dihydroderivative (GYKI 52895, 2) is described. The title compounds have been prepared starting from safrole through a quite effective procedure.

A series of 1,3-benzodioxoles (5-19) was synthesized and evaluated for their in vitro antitumor activity against human tumor cell lines. Some derivatives exhibited tumor growth inhibition activity. In particular, 6-(4-aminobenzoyl)-1,3-benzodioxole-5-acetic acid methyl ester 8, the most active compound of the series, possesses a significant growth inhibitory activity on 52 cell lines at concentrations ranging from 10(-7) to 10(-5) M.

β-Nitrostyrenes are selectively reduced to the corresponding oximes in high yields by indium metal in aqueous methanol under neutral reaction conditions.

The electrochemical reduction of a mixture of aryl halides and activated alkyl halides in DMF in the presence of catalytic amount of NiBr2bipy leads to cross-coupling products in good to high yields. The method applies to the synthesis of α-aryl ketones, α-aryl esters, and allylated compounds from readily available organic halides. Optimization of the process has been obtained by slowly adding the most reactive organic halide (usually the activated alkyl halide) during the electrolysis which is best conducted at 70 °C when aryl bromides are involved.

The electrochemical Wacker type oxidation of terminal olefins by using palladium chloride or palladium acetate and tri(4-bromophenyl)amine as a recyclable mediator in either a divided cell or an undivided cell afforded the corresponding methyl ketones in good yields.

α-Arylated ketones were obtained in moderate to good yields by one-step electroreductive coupling of α-chloroketones and arylhalides in DMF and in the presence of a Al- or Zn-sacrificial anode and a catalytic amount of a nickel complex.

A simple two-step approach to 1-(3,4-dimethoxyphenyl)- and 1-[3,4-(methylenedioxy)phenyl]-2-propanone (4a and 4b), useful intermediates for α-methyldopa, is described. It is based on the epoxidation of the widely available methyleugenol (1-allyl-3,4-dimethoxybenzene, 1a) and safrole [1-allyl-3,4-(methylenedioxy)benzene, 1b] with hydrogen peroxide catalyzed by tungsten peroxo complex 2a under two-phase conditions, followed by isomerization of the intermediate epoxides 3a and 3b by lithium iodide.

The immobilized organoaluminum columns can be successfully utilized as a workup-free reactor for the catalytic rearrangement of various epoxides to carbonyl compounds.

A new, stereocontrolled rearrangement of epoxy silyl ethers leading to β-siloxy aldehydes has been effected with stoichiometric use of exceptionally bulky, oxygenophilic methylaluminum bis(4-bromo-2,6-di-trert-butylphenoxide) (MABR) under mild conditions. Used in combination with the Sharpless asymmetric epoxidation of allylic alcohols, this rearrangement represents a new approach to the synthesis of various optically active β-hydroxy aldehydes, useful intermediates in natural product synthesis. The modified organoaluminum reagent, MABR is also applicable to the transformation of a variety of simple epoxides to carbonyl compounds with high efficiency and selectivity. Further, the catalytic version for the rearrangement of epoxy silyl ethers as well as simple epoxides has been newly devised. The scope and limitation of this catalytic method has been clarified with various epoxy substrates.

The mechanism of demethylenation of (methylenedioxy)benzene (MDB), (methylenedioxy)amphetamine (MDA), and (methylenedioxy)methamphetamine (MDMA) by purified rabbit liver cytochrome P450IIB4 has been investigated by using deuterium isotope effects. A comparison of the magnitude and direction of the observed kinetic isotope effects indicates that the three compounds are demethylenated by different mechanisms. The different mechanisms of demethylenation have been proposed on the basis of comparisons of the observed biochemical isotope effects with the isotope effects from purely chemical systems.

Benzyl ketones of the general formula I STR1 where R1 is C1 -C8 -alkyl which is unsubstituted or substituted by cycloalkyl or aryl and R2 and R3 are each halogen, C1 -C4 -alkyl, hydroxyl, C1 -C4 -alkoxy or C2 -C4 -methylenedioxy, are prepared by a process in which a glycol monoether of the general formula II STR2 where R1, R2 and R3 have the abovementioned meanings and R4 is C1 -C8 -alkyl, is converted in the presence of silica, a phosphate or a zeolite at from 50° to 500° C. and under from 0.01 to 50 bar.

Exceptionally bulky, oxygenophilic methylaluminum bis(4-bromo-2,6-di-tert-butylphenoxide) (reagent A) can be utilized as an active catalyst for the transformation of various epoxides to carbonyl compounds with high efficiency and selectivity.

Process for the preparation of phenylpropanones having formula: STR1 R and R1, equal or different, being C1 -C4 alkyl groups or being coincident in the CH2 group of a heterocyclic ring, wherein the corresponding allylbenzenes are catalytically epoxidized by means of H2 O2, in a biphase system comprising an aqueous phase containing H2 O2 and an organic phase containing said allylbenzenes, a solvent immiscible with said aqueous phase and a catalyst having formula Q3 XW4 O24 (Q being a quaternary cation containing hydrocarbylic groups having on the whole from 20 to 70 C atoms, and X being P or As) and wherein the thus obtained epoxides are isomerized by heating at 90°-150° C., in the presence of catalytic amounts of LiI.

A phenylacetone or its derivative having the general formula (I): STR1 wherein X, Y, and Z are independently a hydrogen atom, a hydroxyl group, a halogen atom, a nitro group, an amino group, a lower alkyl group having 1 to 6 carbon atoms, a lower alkoxy group having 1 to 6 carbon atoms, or a benzyloxy group and any two substituents of X, Y, and Z may form, together with the benzene ring, a heterocycling ring having 5 to 7 members including 1 or 2 oxygen atoms is produced at a high yield and a high selectivity by reacting a 3-phenylpropylene or its derivative having the general formula (II): STR2 wherein X, Y, and Z are as defined above, with an alkyl nitrite having the general formula (III): wherein R is an aliphatic, aromatic, or alicyclic saturated or unsaturated hydrocarbon group in the presence of (a) water, (b) an alcohol, (c) a palladium catalyst, and (d) an optional amine or copper compound, or by reacting the above-mentioned 3-phenylpropylene or its derivative with the above-mentioned alkyl nitrite in the presence of (a) an alcohol, (b) a palladium catalyst and (c) an optional amine or copper compound to form 1-phenyl-2,2-dialkoxypropane or it derivative having the general formula (IV): STR3 wherein X, Y, Z and R are as defined above, followed by hydrolyzing the reaction product.

Pd salts catalyse oxidation of alcohols with CCl4 in the presence of K2CO3. Primary alcohols are oxidised to esters, and secondary alcohols to ketones. CCl4 is converted to CHCl3. The reaction of allylic alcohols bearing a terminal olefinic bond with CCl4 or BrCCl3 in the presence of palladium catalyst at 110° affords 4,4,4-trichloro ketones. At 40°, simple adducts of CCl4 or BrCCl3 having a halohydrin structure are obtained, which are converted to the corresponding trichloro ketones by the catalysis of palladium. Various halohydrins are converted to ketones by Pd catalysis.

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From the extract of Saururus cernuus two toxic principles, manassantins A and B and a related substance, saucerneol, were isolated.They have novel dineolignan or sesquineolignan type structures.Although toxic, manassantin A showed potential neuroleptic activity.

Electrochemical Transformation of epoxides 1 to ketones 2 and acetonides 3 were achieved by using an electrogenerated acid-catalyst.A combination of M(ClO4)n with polar aprotic solvents is useful for the electrochemical transformation.

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Novel preparative methods for arylacetone and arylacetonitrile are described.Friedel-Crafts reactions of aromatic compounds with α-chloro-α-(methylthio)acetone (4) and α-chloro-α-(methylthio)acetonitrile (7) in the presence of Lewis acid afforded α-(methylthio)arylacetone (5) and α-(methylthio)arylacetonitrile (8), respectively.Compounds (5) and (8) were converted into the corresponding arylacetone (6) and arylacetonitrile (9) by reduction with zinc dust in acetic acid.Keywords: Friedel-Crafts reaction with α-chloro-α-(methylthio)acetone; Friedel-Crafts reaction with α-chloro-α-(methylthio)acetonitrile; α-(methylthio)arylacetone; α-(methylthio)arylacetonitrile; arylacetone; arylacetonitrile; reductive desulfurization; zinc dust-acetic acid

Trimethylsilyldiazomethane adds to aromatic aldehydes in the presence of triethylamine in methanolic solution to give epoxides and homologous compounds.

o-Lithio-N-methylbenzamide upon condensation with propylene oxide gives 3-methyldihydroisocoumarin.Similarly o-lithio-N-methyl-p-toluamide upon condensation with ethylene oxide and propylene oxide give 6-methyl- and 3,6-dimethyldihydroisocoumarin.A similar condensation of o-lithio-N-methyl-m-toluamide with ethylene oxide gives 5-methyldihydroisocoumarin but condensation with propylene oxide gives 3,5-dimethyl- and 3,7-dimethyldihydroisocoumarins.The method has been used to synthesize (+/-)-5-methylmellein.The synthesis of 5,6-methylenedioxydihydroisocoumarin from o-lithio-N-methylpiperonylamide is also described. 3-Methyl-6,7-methylenedioxydihydroisocoumarin has been synthesized by an acid-catalyzed cyclization reaction.

Oxidation of 4-allylphenols in MeOH has been carried out using thallium (III) nitrate to give two different types of reaction product.In the cases of 4-allylphenols with an electron-donating group (MeO), methoxylation takes place on the aromatic ring resulting in the formation of asatone-type compound as well as of 2,5-cyclohexadien-1-one.In the case of 4-allyl-2-methoxy-6-nitrophenol, however, the allyl group was attacked by the reagent to give three phenols.