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A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.

In this work, a visible-light-induced oxidative α-alkylation of glycine derivatives with ethers has been developed in the presence of catalytic Eosin Y. Under the blue light of a 3 W LED, a range of α-etherized glycine derivatives, including α-amino esters, α-amino ketones and α-amino amides, were achieved with good to excellent yields and functional group tolerance with tert-butyl hydroperoxide (TBHP) as oxidant at ambient temperature. The operationally easy procedure provides an economical, metal-free, and mild alternative for the synthesis of the α-etherized glycine derivatives.

Phosphine-catalyzed tandem Michael addition/intramolecular Wittig reactions have been developed for the synthesis of chiral 2,5-dihydro-1H-pyrrole and tetrahydropyridine derivatives. These processes have been rendered catalytic in phosphine, thanks to the in situ reduction of phosphine oxide by phenylsilane. Furthermore, catalytic and asymmetric P(III)/P(V) processes were implemented using enantiopure chiral phosphines.

Thirty-five new colchicine binding site inhibitors have been designed and synthesized based on the 1,2,4-triazin-3(2H)-one nucleus. Such molecules were synthesized through a cascade reaction between readily accessible α-amino ketones and phenyl carbazate

A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C-N and N-N bond formation has been demonstrated under transition metal-free and azide-free conditions. These 1,2,3-triazoles were obtained in a regioselective manner from commercially available anilines, aryl alkenes/aryl alkynes and N-tosylhydrazines using I2 under O2 atmosphere. Broad substrate scope, milder reaction conditions, good to moderate yields and clean protocol are the notable features of the method. Moreover, this protocol is amenable for the generation of a library of medicinally important key building blocks.

A versatile route has been developed for the synthesis of 2-arylindoles using a Pd-catalyzed tandem process. Under reductive conditions, different 2-arylindoles were synthesized from phenylglyoxal and aniline. This synthetic methodology involves a tandem reaction of four steps with high regioselectivity. Alternatively, 2-anilinoacetophenones intermediates also can be using to give access to the corresponding 2-arylindoles.

An efficient, one-pot and three-component synthesis of a new series of 2-acyl-3,4,6-triaryl-1,4-dihydropyrazines is described. This two-step strategy involves treatment of phenacyl bromides and anilines to give the nucleophilic substitution intermediate f

A novel copper-catalyzed cross-dehydrogenative coupling reaction of α-amino carbonyl compounds with nitromethane to synthesis of (Z)-nitroalkene derivatives has been established. (Z)-Nitroalkene derivatives are achieved through the cleavage of sp3 CsbndH bonds and formation of CsbndC double bond, with mild reaction conditions and excellent stereoselectivity.

The enantioselective reduction of α-hydroxy ketones with catecholborane has been developed employing 5 mol% of an 1,1′-bi-2-naphthol (BINOL)-derived ion-pair organocatalyst. This methodology provides a straightforward access to the corresponding aromatic 1,2-diols in high yields (up to 90%) with excellent enantioselectivities (up to 97%). Furthermore, the α-amino ketones also could be reduced with moderate ee values under mild reaction condition. (Figure presented.).

A general and mild method for the construction of a carbon-nitrogen bond via copper-catalyzed oxidative cross-coupling of amines with α-aminocarbonyl compounds was achieved. Amines, either aliphatic primary amines, aromatic primary amines or secondary amines can be used as the starting materials. When R2 was different from R3, two isomers would be observed. Therefore, this reaction system has a broad substrate scope and provides a facile pathway for the synthesis of 2-oxo-acetamidines.

Described herein are compounds, methods of making such compounds, pharmaceutical compositions and medicaments containing such compounds, and methods of using such compounds to treat or prevent diseases or disorders associated with the enzyme ceramide galactosyltransferase (CGT), such as, for example, lysosomal storage diseases. Examples of lysosomal storage diseases include, for example, Krabbe disease and Metachromatic Leukodystrophy.

Metal carbenes can undergo a myriad of synthetic transformations. Sulfur ylides are potential safe precursors of metal carbenes. Herein, we report cascade reactions that involve carbenoids derived from sulfoxonium ylides for the efficient and regioselective synthesis of indoles and pyrroles. The tandem action of iridium and Br?nsted acid catalysts enables rapid assembly of the heterocycles from unmodified anilines or readily accessible enamines under microwave irradiation. The key mechanistic steps are the catalytic transformation of the sulfoxonium ylide into an iridium–carbene complex, followed by N?H or C?H functionalization of an aniline or enamine, respectively, and a final acid-catalyzed cyclization. The present method was successfully applied to the synthesis of the densely functionalized pyrrole subunit of atorvastatin.

Catalyst systems and methods for making and using the same are provided. A method for forming a polymer catalyst includes reacting a bromoketone compound with an aryl amine compound to form an amide compound. The amide compound is reacted with an ethylene diamine compound, to form a terminal primary amine compound. The terminal primary amine compound is reacted with a bromoaryl compound to form a ligand.

A mild and general α-arylation of α-amino carbonyls with indoles catalyzed by Fe(ClO4)3 has been developed. C-H activation is smoothly fulfilled by using TBHP as the oxidant with good yields. Two hydrogen dissociations make this transformation more environmentally benign because of high atom efficiency.

Two different heterocycles, thiazole-2-imines and imidazole-2-thiones, have been conveniently synthesized by just altering the sequential order (1+2+3 or 1+3+2) when combining the same components [aryl amine (1), aryl isothiocyanate (2), and phenacyl bromide (3)] in one-pot, three-component protocols. The third possible sequential order of combination (2+3+1) chemoselectively affords thiazole-2-imine. The finding is a stepping stone in the synthetic applicability of sequential one-pot, three-component protocols.

Visible light-mediated photoredox catalysis enables the chemoselective reduction of activated carbon–heteroatom bonds as a function of reduction potential. The expansion of the scope of C–X bond reductions towards less activated motifs, such as ethers, amines and sulfides, is important to both organic synthesis and macromolecular degradation method development. In the present report, exploration of photoredox catalysis in alcoholic solvents mediated a decrease in the super-stoichiometric use of iPr2NEt and HCO2H in the reduction of α-keto ethers, amines and sulfides. Additionally, in the absence of fragmentation, [Formula presented] bond formation was afforded, suggesting an intermediate ketyl radicals are present in these transformations.

An efficient synthesis of 2-(perfluoroalkyl)pyrroles that employs a sequential one-pot three-component reaction between substituted ω-bromoacetophenones, anilines, and methyl perfluoroalk-2-ynoates has been developed. This transition-metal-free cascade pr

A gold-catalyzed cascade hydroamination/cyclization reaction of α-amino ketones with alkynes to form substituted pyrroles has been developed. The method offers several advantages such as high regioselectivity with the tested cases, wide functional group tolerance, and easily accessible starting materials. The synthetic utility of the obtained pyrrole products was demonstrated by their efficient transformations to 2-vinylated pyrroles via gold-catalyzed intermolecular hydroarylation.

1,4-Benzodiazepin-5-ones were synthesized in 71-89% yields from 2-isocyanato-N-(2-oxoalkyl)benzamides via a new catalytic intramolecular aza-Wittig reaction. Starting from easily accessible phthalic anhydride and α-arylamino ketones, the corresponding 2-{[(2-oxoalkyl)amino]carbonyl}benzoic acids underwent sequential formation of the acid azide and Curtis rearrangement to give 2-isocyanato-N-(2-oxoalkyl)benzamides that were reacted directly to give the final 2,4-diaryl-3,4-dihydro-5H-1,4-benzodiazepin-5-ones and 4-aryl-2-tert-butyl-3,4-dihydro-5H-1,4-benzodiazepin-5-ones.

Aldehyde-bisulfite adducts dervied from unstable parent aldehydes were reductively alkylated in a direct fashion with a variety of amines. This approach features the use of 2-picoline borane as the reducing agent and a protic solvent for the reaction media and has been successfully applied to the synthesis of a DPP-IV inhibitor and a variety of other amines.

NNNifty targets: In a straightforward copper-mediated synthesis of 1,4-disubstituted and 1,4,5-trisubstituted 1,2,3-triazoles, readily available aniline and N-tosylhydrazone substrates underwent cyclization through Ci￡N and Ni￡N bond formation (see scheme

A number of optically active amino alcohols were synthesized by direct asymmetric transfer hydrogenation of the corresponding amino ketones with good-to-high enantiomeric excesses (up to 95%) and excellent yields (up to 93%). When the range of substrates was broadened to include α-sulfonamido ketones or α-keto sulfones, the corresponding products were obtained with 100% enantiomeric excesses. The absolute configuration of (1R)-2-[(4- chlorophenyl) amino]-1-(4-methoxyphenyl) ethanol was confirmed by X-ray crystal structure analysis. Georg Thieme Verlag Stuttgart.

The asymmetric addition of diazoacetophenone to styrene derivatives to give optically active cyclopropyl ketones (ee up to 80%) was carried out using chiral iron porphyrins as homogeneous catalysts. Intermolecular N-H functionalization of anilines by mean

Imidazolines substituted at the 1- and either the 4-, or 5-position with phenyl and at the 2-position with alkyl or phenyl have been prepared in racemic form. They appear to be fairly stable compounds and potentially useful as scaffolds in medicinal chemistry. Georg Thieme Verlag Stuttgart.

The phenacyl group can be introduced onto amino and thio groups by N,S-alkylation reactions. Conversely, these groups are removed rapidly by employing magnesium in acetic acid. This protecting group was successfully applied to a short peptide synthesis of Boc-L-Cys-Gly-OMe. Georg Thieme Verlag Stuttgart.

The solid-state reaction between anilines and phenacyl bromides in the presence of an equimolecular amount of sodium bicarbonate gives N-phenacylanilines. Microwave irradiation of mixtures of these compounds with anilinium bromides at 540 W for 45-60 s provides a mild, general, and environmentally friendly method for the synthesis of 2-arylindoles in 50-56% overall yields. A one-pot variation of the method, involving irradiation of 2:1 mixtures of anilines and phenacyl bromides, was also developed, allowing a simplified experimental procedure and leading to improved yields (52-75%). Georg Thieme Verlag Stuttgart.

1,8-Diazabicyclo[5.4.0]undec-7ene (DBU) facilitated the oxidative cyclization of phenacyl amide in the presence of atmospheric oxygen under environmentally friendly conditions. The reaction has been studied under various conditions and a plausible mechani

Photochemically induced reductive ring contractions, previously observed for 2,5-dihydro-1,2,4-triazines, have also been verified for 1,4-dihydropyrimidines 2a,b, the dihydro-1,2,4,5-tetrazine 9, and dihydro-1,3,5-triazines 11a,b giving rise to fivemembered fully unsaturated heterocycles (pyrroles 4a,b, imidazoles 13a,b, and triazole 10, respectively). The 1,4-dihydropyrazines 15a-j tend to decompose in acidified 2-propanol in the dark, but on irradiation they also undergo reductive ring contraction furnishing solely the 1,2,5-triarylpyrroles 16a-d rather than the (a priori also possible) isomeric 1,3,4-triarylpyrroles 17a-d. In contrast, the 3,6-diphenylpyrid-azine 18 gives the 4-isopropyl-analogue 19 in low yield upon irradiation in hydrogen chloride saturated 2-propanol. Wiley-VCH Verlag GmbH, 2000.

5,7-Diphenyl-pyrrolo[2,3d]pyrimidines represent a new class of highly potent inhibitors of the tyrosine kinase c-Src (IC50 50 nM) with specificity against a panel of different tyrosine kinases. The substitution pattern on the two phenyl rings

A general method for the synthesis of the title compounds is reported.The N-phenacylarylamines (11), prepared from the corresponding phenacyl bromides (9) and arylamines (10), give the thiono (or dithio) carbamates (12) on treatment with phenoxythionocarb

An improved procedure for the preparation of ethyl 2-diazomalonyl chloride was developed which involves the reaction of ethyl diazoacetate with triphosgene.Using this diazo acid chloride, it was possible to prepare a variety of diazoamides from substituted amines.The rhodium(II)-catalyzed decomposition of these diazoamides was studied in order to probe the chemoselectivity of the carbenoid intermediates in intramolecular insertion reactions.Rhodium(II) acetate decomposition of N-benzyl-2-diazo-N-phenylmalonamic acid ethyl ester resulted in intramolecular C-H insertion to give ethyl 1,4-diphenyl-2-oxoazetidine-3-carboxylate.By changing the catalyst ligand to trifluoroacetamide, β-lactam formation was completely suppressed in favor of the aromatic C-H insertion which produces an oxindole as the only detectable product.The competition between aliphatic and aromatic carbon-hydrogen insertion of 2-diazo-N-isobutyl-N-phenylmalonamic acid ethyl ester provides another example of ligand effectiveness in controlling chemoselectivity in dirhodium(II)-catalyzed metal carbene reactions.Thus, treatment of the N-isobutyldiazoanilide with rhodium(II) acetate results in exclusive aliphatic C-H insertion giving 4,4-dimethyl-2-oxo-1-phenylpyrrolidine-3-carboxylic acid ethyl ester, while the perfluorobutyramide ligand promotes oxindole formation by aromatic C-H insertion.Several other rhodium(II)-catalyzed reactions were studied and were found to be highly catalyst dependent, rhodium(II) perfluorocarboxamides promoting aromatic C-H insertion, and hence oxindole formation, over O-H insertion, cyclization onto adjacent triple bonds, or cyclization to generate 1,3-dipolar intermediates.

Successive treatment of acetophenones (1a-e) or 2-acetylthiophene (4) with benzene, appropriate aniline and KSCN/AcOH leads to the formation of 1,4-diaryl-2-mercaptoimidazoles (3aa-3ea) or 1-aryl-2-mercapto-4-(2-thienyl)imidazoles (6a-f) respectively.This procedure also provides 2(α-anilinoacetyl)thiophenes (5a-f) in one pot from 4.

Hypervalent iodine oxidation of acetophenones (1) with benzene, followed by treatment with appropriate aniline, provides a new, convenient and useful route to the synthesis of α-anilinoacetophenones (3a-h).

The kinetics of the reaction of α-bromoacetophenone and benzyl bromide with aniline and pyridine in the presence of additions of acetic acid and phenol in benzene at 30 deg C were investigated.The catalytic effect due to the activity of the uncombined forms of the catalyst, their dimers, and their 1:1 complexes with the amines were separated quantitatively.The change in the catalytic activity of the respective particles in the solutions with variation in the structure of the reagents is examined, and possible mechanisms for the catalytic reactions are discussed on this basis.It is concluded that there is a bifunctional mechanism of catalysis by acetic acid in the reaction of α-bromoacetophenone with aniline.

The nucleophilic substitution reactions of phenacyl benzenesulphonates with anilines in methanol-acetonitrile have been studied.A stronger nucleophile was found to cause less bond cleavage, while a better leaving group led to less bond formation, in compl

The N-phenacylarylamine (4) gives the N,N-diphenacyl derivative (5) on treatment with phenacyl bromine under phase-transfer catalysis conditions.Condensation of (5) with an arylamine results in the formation of the thermally stable 1,4-diaryl-3,5-diphenyl

The rates of reactions of ethyl bromoacetate, phenacyl bromide, and allyl bromide with aniline and m- and p-substituted anilines and 1- and 2-naphthylamines have been measured in 90percent acetone-10percent water (v/v) mixture at three temperatures.The reactivities of the bromo compounds follow the order: phenacyl bromide > allyl bromide > ethyl bromoacetate.All the reactions show excellent correlations with Hammett ? constants.Broensted-type plots of log k2 versus pKa for the SN2 reactions of ethyl bromoacetate and phenacyl bromide with anilines give parallel lines with slopes (βN) around 0.8 and hence it is concluded that the extent of C-N bond making in the transition state remains constant in these two series of reactions, while the lower value of βN(ca. 0.6) for allyl bromide indicates that the extent of bond formation is less.

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