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Multi-drug resistant (MDR) bacteria are already a significant health-care problem and are making the combat of infections quite challenging. Here we report the synthesis of several new compounds containing an ethanolamine moiety, of which two exhibit prom

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.).

We report here the remarkable and non-catalytic beneficial effects of a Ni(II) ion binding to a Si|PNP type surface as a result of significant thermodynamic band bending induced by ligand attachment and Ni(II) binding. We unambiguously deconvolute the thermodynamic flat band potentials (VFB) from the kinetic onset potentials (Von) by synthesizing a specialized bis-PNP macrochelate that enables one-step Ni(II) binding to a p-Si(111) substrate. XPS analysis and rigorous control experiments confirm covalent attachment of the designed ligand and its resulting Ni(II) complex. Illuminated J-V measurements under catalytic conditions show that the Si|BisPNP-Ni substrate exhibits the most positive onset potential for the hydrogen evolution reaction (HER) (-0.55 V vs Fc/Fc+) compared to other substrates herein. Thermodynamic flat band potential measurements in the dark reveal that Si|BisPNP-Ni also exhibits the most positive VFB value (-0.02 V vs Fc/Fc+) by a wide margin. Electrochemical impedance spectroscopy data generated under illuminated, catalytic conditions demonstrate a surprising lack of correlation evident between Von and equivalent circuit element parameters commonly associated with HER. Overall, the resulting paradigm comprises a system wherein the extent of band bending induced by metal ion binding is the primary driver of photoelectrochemical (PEC)-HER benefits, while the kinetic (catalytic) effects of the PNP-Ni(II) are minimal. This suggests that dipole and band-edge engineering must be a primary design consideration (not secondary to catalyst) in semiconductor|catalyst hybrids for PEC-HER.

Dehydrogenative silylation of alkenes with silanes to produce allylsilanes is achieved through manganese catalysis with a wide scope of substrate tolerance. This transformation involves silane radicals initiated by manganese complex without additional oxidant additives. It offers a general, convenient and practical protocol with excellent functional group compatibility and gram-scale capacity for the modular synthesis of allylsilanes.

A method for the cross-coupling reactions of aryldiazonium salts with trialkylallylsilanes via merged gold/photoredox catalysis is described. The reaction is proposed to proceed through a photoredox-promoted generation of an electrophilic arylgold(III) intermediate that undergoes transmetalation with allyltrimethylsilane to form allylarenes.

Cationic rearrangement reactions usually follow Markovnikov's rule to give more substituted carbocations as stable intermediates. During our study on sulfur mediated allylic C-H amination of olefins, very rare cases of anti-Markovnikov rearrangement from secondary carbocations toward primary carbocations or primary triflates were observed.

The present invention relates to compounds Formula (I) as inhibitors of AKT activity, which are useful for the treatment of susceptible neoplasms and viral infections.

The Pd-catalyzed cross-coupling reaction of aromatic iodides and bromides with allylboronic acid esters (2a,b) in the presence of CsF gave allylated aromatics. Georg Thieme Verlag Stuttgart.

Electrophilic nitration of benzylcyclopropanes, allylbenzenes, and diphenylmethanes containing ortho, para-orienting substituents in the para position of the benzene ring results mainly in replacement of the cyclopropylmethyl, allyl, or benzyl group, respectively (ipso substitution). The nitration of 4-cyclopropylallylbenzene is not accompanied by nitrodealkylation, and the products are only 2- and 3-nitro-4-cyclopropylallylbenzenes.

(Chemical Equation Presented) The photolysis of a series of 4-X-benzenediazonium tetrafluoroborates is studied in MeCN. Loss of nitrogen occurs from the singlet excited state with X = H, t-Bu, and NMe2 and leads to the singlet aryl cation. This adds to the solvent yielding the corresponding acetanilides. With other substituents, ISC competes with (X = Br, CN) or overcomes (X = COMe, NO2) fragmentation and the aryl cation is formed in part or completely in the triplet state. In neat MeCN, this either abstracts hydrogen from the solvent (in most cases inefficiently) or undergoes intersystem crossing to the more stable singlet that reacts as above. In the presence of π nucleophiles (allyltrimethylsilane or benzene), the triplet aryl cation is efficiently trapped giving substituted allylbenzenes and biphenyls, respectively. By triplet sensitization by xanthone, the triplet cation and the products from it are obtained from the whole series considered. The direct or sensitized photodecomposition of diazonium fluoroborates, substituted with both electron-donating and -withdrawing substituents, in the presence of alkenes and arenes offers an access to an alternative arylation procedure.

The Stille coupling of organostannanes and organohalides, mediated by air and moisture stable palladium(II) phosphine complexes containing succinimide or phthalimide (imidate) ligands, has been investigated. An efficient synthetic route to several palladium(II) complexes containing succinimide and phthalimide ligands, has been developed. cis-Bromobis(triphenylphosphine)(N-succinimide) palladium(II) [(Ph3P)2Pd(N-Succ)Br] is shown to mediate the Stille coupling of allylic and benzylic halides with alkenyl, aryl and allyl stannanes. In competition experiments between 4-nitrobromobenzene and benzyl bromide with a cis-stannylvinyl ester, (Ph3P)2Pd(N-Succ)Br preferentially cross-couples benzyl bromide, whereas with other commonly employed precatalysts 4-nitrobromobenzene undergoes preferential cross-coupling. Furthermore, preferential reaction of deactivated benzyl bromides over activated benzyl bromides is observed for the first time. The type of halide and presence of a succinimide ligand are essential for effective Stille coupling. The type of phosphine ligand is also shown to alter the catalytic activity of palladium(II) succinimide complexes.

Allylic and benzylic bromides are cross-coupled with organostannanes efficiently using the precatalyst [Pd(NCOC2H4CO)(PPh 3)2Br] 1. Significantly, these reactions do not require the use of hexamethylphosphoramide (HMPA) as the solvent, or additional ligands, such as trifurylphosphine or triphenylarsine. Selectivity for benzyl bromide over bromobenzene is observed for precatalyst 1, against the precatalysts, bromobis(triphenylphosphine)(benzyl)palladium(II) and bis(triphenylphosphine) palladium(II) bromide.

The photodediazoniation of some 4-X-phenyldiazonium tetrafluoborates in MeCN leads to the singlet phenyl cations (X = H, tert-butyl, NMe2, CN), which add to the solvent yielding the corresponding acetanilides. Triplet sensitisation, however, leads to the triplet phenyl cation, which is reduced in neat solvent and is trapped by π nucleophiles (allyltrimethylsilane and benzene), resulting in an ionic analogue of the Meerwein or Gomberg arylations. With the 4-nitro derivative intersystem crossing prevails over dediazoniation from the singlet and with the 4-cyano competes with it, so that in those cases the triplet phenyl cation is formed also upon direct irradiation.

A new method for the synthesis of allyl aromatic compounds not involving any metal-containing reagent or catalyst has been developed. Arylamines substituted with a large number of different substituents were converted via diazotizative deamination with tert-butyl nitrite in allyl bromide and acetonitrile to the corresponding allyl aromatic compounds. The allylation reaction was found to be suitable for larger scale synthesis due to short reaction times, a nonextractive workup, and robustness toward moisture, air, and type of solvent.

A process for the preparation of an allylic aromatic compound in which an aromatic amine is reacted first with a nitrite and then with an allylic olefin having an eliminatable terminal substituent. Novel allylic derivatives of disubstituted benzene compou

The reactivity of some functionalized azides has been studied under the conditions of the Staudinger and aza-Wittig reactions. With the azides having a trifluoroacetamido group in the ortho-position of the aromatic ring, intramolecular reactions have been observed which allow new synthetic approaches to indoline and imidazoindole compounds.

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