The Palladium-Catalyzed Cross-Coupling Reaction of Phenylboronic Acid with Haloarenes in the Presence of Bases

Synthesis and catalytic activity of a poly(N,N-dialkylcarbodiimide)/palladium nanoparticle composite: a case in the Suzuki coupling reaction using microwave and conventional heating

Poly(N,N-dialkylcarbodiimide) was found to be an effective polymeric ligand system for preparing and stabilizing palladium nanoparticles (1-5 nm). The composite material prepared in situ was found to be a robust catalyst for the Suzuki coupling reaction under microwave or regular heating.

Hexakis(4-iodophenyl)-peri-hexabenzocoronene- A Versatile Building Block for Highly Ordered Discotic Liquid Crystalline Materials

Hexakis (4-iodophenyl)-peri-hexabenzocoronene (5), a novel functionalizable mesogenic building block, was prepared by rational multistep synthesis. Although sparingly soluble in common solvents, it can be obtained in pure form and then functionalized via Hagihara-Sonogashira coupling to give a series of highly ordered columnar liquid crystalline molecules 14a-c. The total synthesis involves five 6-fold transformations, all in excellent to near quantitative isolated yields. Their thermotropic liquid crystalline behavior was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD). Compared to the normal alkyl-subsituted hexabenzocoronenes (HBCs), 14a-c exhibit more highly ordered columnar mesophases, including three-dimensionally ordered superstructures (helical columnar mesophase). These could arise from additional intracolumnar pi-pi interactions between, and space-filling requirements introduced by, the rigid-rod side groups. Atomic force microscopy (AFM) revealed self-assembled bundles of columnar aggregates in spin-coated films and isolated several-micron-long nanoribbons composed of a defined number of columns in drop cast films.

Diflunisal Analogues Stabilize the Native State of Transthyretin. Potent Inhibition of Amyloidogenesis

Analogues of diflunisal, an FDA-approved nonsteroidal antiinflammatory drug (NSAID), were synthesized and evaluated as inhibitors of transthyretin (TTR) aggregation, including amyloid fibril formation. High inhibitory activity was observed for 26 of the compounds. Of those, eight exhibited excellent binding selectivity for TTR in human plasma (binding stoichiometry >0.50, with a theoretical maximum of 2.0 inhibitors bound per TTR tetramer). Biophysical studies reveal that these eight inhibitors dramatically slow tetramer dissociation (the rate-determining step of amyloidogenesis) over a duration of 168 h. This appears to be achieved through ground-state stabilization, which raises the kinetic barrier for tetramer dissociation. Kinetic stabilization of WT TTR by these eight inhibitors is further substantiated by the decreasing rate of amyloid fibril formation as a function of increasing inhibitor concentration (pH 4.4). X-ray cocrystal structures of the TTR.18(2) and TTR.20(2) complexes reveal that 18 and 20 bind in opposite orientations in the TTR binding site. Moving the fluorines from the meta positions in 18 to the ortho positions in 20 reverses the binding orientation, allowing the hydrophilic aromatic ring of 20 to orient in the outer binding pocket where the carboxylate engages in favorable electrostatic interactions with the epsilon-ammonium groups of Lys 15 and 15'. The hydrophilic aryl ring of 18 occupies the inner binding pocket, with the carboxylate positioned to hydrogen bond to the serine 117 and 117' residues. Diflunisal itself appears to occupy both orientations based on the electron density in the TTR.1(2) structure. Structure-activity relationships reveal that para-carboxylate substitution on the hydrophilic ring and dihalogen substitution on the hydrophobic ring afford the most active TTR amyloid inhibitors.

Synthesis of Polyfunctionalized Biphenyls as Intermediates for a New Class of Liquid Crystals

A series of hexa- and octasubstituted biphenyls containing halogen, amino, nitro, and propylthio substituents were prepared by metal-mediated convergent synthesis from halobenzene precursors. The Pd-assisted C-C coupling methods were ineffective in the formation of the Ar-Ar bond except for the synthesis of 1b. All tetra-ortho-substituted biphenyls were prepared via Ullmann coupling reactions. The halogens were introduced after formation of the biphenyl by utilizing the directing properties of the amino group(s). In the case of 3b, a polyhalogenated benzene substrate was used for biphenyl formation via Ullmann coupling.

Palladium Charcoal-Catalyzed Suzuki−Miyaura Coupling To Obtain Arylpyridines and Arylquinolines

A phosphine ligand, such as PPh3 or 2-(dicyclohexylphosphino)biphenyl, is essential for the Pd/C-catalyzed Suzuki-Miyaura coupling of halopyridines and haloquinolines, although it has been reported that the reaction of phenyl chlorides can be catalyzed by nonprereduced Pd/C without any additives. In the reactions of bromopyridines, bromoquinolines, 2-chloropyridines, and 2-chloroquinolines, PPh3 was effective enough to provide coupling products in good yields. However, in the reactions of 3-chloropyridine, 4-chloropyridine, and 6-chloroquinoline, sterically hindered 2-(dicyclohexylphosphino)biphenyl was indispensable as a ligand.

Development of novel steroid sulfatase inhibitors. I. Synthesis and biological evaluation of biphenyl-4-O-sulfamates

Compounds which interfere with steroid sulfatase (STS) are expected as important novel therapeutic drugs for postmenopausal breast tumor. Therefore, a number of strategies have been adopted to design and synthesize potent, nonestrogenic STS inhibitors. We chose biphenyl as a scaffold for STS inhibitors and synthesized some biphenyl-4-O-sulfamate derivatives (29-43). Their inhibitory activity on STS and estrogenicity were evaluated. Substitution of electron-withdrawing groups (e.g., cyano, nitro) at the 2'- or 4'-position of biphenyl-4-O-sulfamate remarkably increased STS-inhibitory activity. Especially, 2',4'-dicyanobiphenyl-4-O-sulfamate (35, TZS-8478) showed very potent STS-inhibitory activity in vitro. The administration of TZS-8478 (0.5 mg/kg per day, p.o., for 5 days) completely inhibited rat liver and uterine STS similarly to EMATE (1). Furthermore, TZS-8478 (10 mg/kg per day, p.o., for 5 days) had no stimulative effect on uterine growth in ovariectomized rats, and its desulfamoylated compound (20) was little bound to the human estrogen receptor alpha. The identification of a potent steroid sulfatase inhibitor without estrogenicity, such as TZS-8478, should be of considerable value in evaluating the potential of steroid sulfatase inhibition for breast tumor therapy.

Facile Preparation of Optically Pure 7,7‘-Disubstituted BINOLs and Their Application in Asymmetric Catalysis

A family of optically pure 7,7'-disubsituted-2,2'-dihydroxy-1,1'-dinaphthyls have been conveniently prepared from easily accessible 7-alloxyl-2-naphthol by reaction sequences beginning with the asymmetric oxidative coupling and followed by key synthetic steps including deprotection, alkylation, and Suzuki coupling. Application of these binaphthols in catalytic phenylacetylene addition to aldehydes resulted in excellent enantioselectivities.

5-benzylidene-1,2-dihydrochromeno[3,4-f]quinolines as selective progesterone receptor modulators

A series of 5-benylidene-1,2-dihydrochromeno[3,4-f]quinolines (4) were synthesized and tested in bioassays to evaluate their progestational activities, receptor- and tissue-selectivity profiles as selective progesterone receptor modulators (SPRMs). Most of the new analogues exhibited as highly potent progestins with more than 100-fold receptor selectivity over other steroid hormone receptors and LG120920 (7b) demonstrated tissue selectivity toward uterus and vagina versus breasts in a rodent model after oral administration.

Calamitic bolaamphiphiles with (semi)perfluorinated lateral chains: polyphilic block molecules with new liquid crystalline phase structures

Novel bolaamphiphiles consisting of a rigid biphenyl unit, two terminal polar 1,2-diol units and laterally attached (semi)perfluorinated chains have been synthesized via palladium-catalyzed cross coupling reactions as the key step. The thermotropic liquid crystalline behavior of these compounds was investigated by polarized light optical microscopy, DSC, and X-ray scattering, and the influences of the length, number, structure, and position of the lateral chain on the mesomorphic properties were studied. A wide variety of unique liquid crystalline phases were found upon elongation of the lateral semiperfluorinated chains. For short- and medium-chain length a series of columnar phases were observed, and upon further elongation of the lateral chain a series of novel mesophases with layer structures were found. In the columnar phases, the nonpolar lateral chains segregate into columns, which are embedded in honeycomb-like networks of cylinders consisting of the biphenyl units. Strings of hydrogen-bonding networks of the diol groups provide cohesive forces, which maintain the overall structure. Changing the length of the lateral chains influences the diameter of the columns and thus determines the number of biphenyl units which are required to surround these columns. The number of these units [four (c2mm, p4mm), five (p2gg), six (p6mm), eight (c2mm) or 10 (p2gg)] defines the shape of the cylinders as well as the lattice type of the columnar phase. It is proposed that the columnar phases with a p2gg lattice result from the regular organization of pairs of cylinders which have a pentagonal cross sectional shape. In the mesophases with layer structure the aromatic rodlike cores are arranged parallel to the layer planes, and the onset of orientational and positional ordering of the biphenyl segments leads to a sequence of subtypes for these lamellar phases (Lam(Iso)-Lam(N)-Lam(X)).

Novel ligands for the opioid receptors: synthesis and structure-activity relationships among 5'-aryl and 5'-heteroaryl 17-cyclopropylmethyl-4,5 alpha-epoxypyrido[2',3':6,7]morphinans

A series of pyridomorphinans possessing an aryl (10a-s) or heteroaryl (11a-h) substituent at the 5'-position of the pyridine ring of 17-cyclopropylmethyl-4,5 alpha-epoxypyrido[2',3':6,7]morphinan was synthesized and evaluated for binding and functional activity at the opioid delta, mu, and kappa receptors. All of these pyridomorphinans bound with higher affinity at the delta site than at mu or kappa sites. The binding data on isomeric compounds revealed that there exists greater bulk tolerance for substituents placed at the o-position of the phenyl ring than at m- or p-positions. Among the ligands examined, the 2-chlorophenyl (10l), 2-nitrophenyl (10n), 2-pyridyl (11a), and 4-quinolinyl (11g) compounds bound to the delta receptor with subnanomolar affinity. Compound 10c with the p-tolyl substituent displayed the highest mu/delta selectivity (ratio=42) whereas compound 10l with the 2-chlorophenyl substituent displayed the highest kappa/delta selectivity (ratio=23). At 10 microM concentration, the in vitro functional activity determined using [(35)S]GTP-gamma-S binding assays showed that all of the compounds were antagonists devoid of any significant agonist activity at the delta, mu, and kappa receptors. Antagonist potency determinations of three selected ligands revealed that the p-tolyl compound 10c is a potent delta selective antagonist. In the [(35)S]GTP-gamma-S assays this compound had a functional antagonist K(i) value of 0.2, 4.52, and 7.62 nM at the delta, mu, and kappa receptors, respectively. In the smooth muscle assays 10c displayed delta antagonist potency with a K(e) value of 0.88 nM. As an antagonist, it was 70-fold more potent at the delta receptors in the MVD than at the mu receptors in the GPI. The in vitro delta antagonist profile of this pyridomorphinan 10c resembles that of the widely used delta selective antagonist ligand naltrindole.

Effect of catalysis on the stability of metallic nanoparticles: Suzuki reaction catalyzed by PVP-palladium nanoparticles

The small size of nanoparticles makes them attractive in catalysis due to their large surface-to-volume ratio. However, being small raises questions about their stability in the harsh chemical environment in which these nanoparticles find themselves during their catalytic function. In the present work, we studied the Suzuki reaction between phenylboronic acid and iodobenzene catalyzed by PVP-Pd nanoparticles to investigate the effect of catalysis, recycling, and the different individual chemicals on the stability and catalytic activity of the nanoparticles during this harsh reaction. The stability of the nanoparticles to the different perturbations is assessed using TEM, and the changes in the catalytic activity are assessed using HPLC analysis of the product yield. It was found that the process of refluxing the nanoparticles for 12 h during the Suzuki catalytic reaction increases the average size and the width of the distribution of the nanoparticles. This was attributed to Ostwald ripening in which the small nanoparticles dissolve to form larger nanoparticles. The kinetics of the change in the nanoparticle size during the 12 h period show that the nanoparticles increase in size during the beginning of the reaction and level off toward the end of the first cycle. When the nanoparticles are recycled for the second cycle, the average size decreases. This could be due to the larger nanoparticles aggregating and precipitating out of solution. This process could also explain the observed loss of the catalytic efficiency of the nanoparticles during the second cycle. It is also found that the addition of biphenyl to the reaction mixture results in it poisoning the active sites and giving rise to a low product yield. The addition of excess PVP stabilizer to the reaction mixture seems to lead to the stability of the nanoparticle surface and size, perhaps due to the inhibition of the Ostwald ripening process. This also decreases the catalytic efficiency of the nanoparticles due to capping of the nanoparticle surface. The addition of phenylboronic acid is found to lead to the stability of the size distribution as it binds to the particle surface through the O(-) of the OH group and acts as a stabilizer. Iodobenzene is found to have no effect and thus probably does not bind strongly to the surface during the catalytic process. These two results might have an implication on the catalytic mechanism of this reaction.

Synthesis of radiolabeled biphenylsulfonamide matrix metalloproteinase inhibitors as new potential PET cancer imaging agents

Novel matrix metalloproteinase (MMP) inhibitor radiotracers, (S)-3-methyl-2-(2',3',4'-methoxybiphenyl-4-sulfonylamino)-butyric acid [(11)C]methyl ester (1a-c), (S)-3-methyl-2-(2',3',4'-fluorobiphenyl-4-sulfonylamino)-butyric acid [(11)C]methyl ester (1d-f), and (S)-3-methyl-2-(4'-nitrobiphenyl-4-sulfonylamino)-butyric acid [(11)C]methyl ester (1g), a series of substituted biphenylsulfonamide derivatives, have been synthesized for evaluation as new potential positron emission tomography (PET) cancer imaging agents.

Design and synthesis of highly potent benzodiazepine gamma-secretase inhibitors: preparation of (2S,3R)-3-(3,4-difluorophenyl)-2-(4-fluorophenyl)-4- hydroxy-N-((3S)-1-methyl-2-oxo-5- phenyl-2,3-dihydro-1H-benzo[e][1,4]-diazepin-3-yl)butyramide by use of an asymmetric Ireland-Claisen rearrangement

Novel benzodiazepine-containing gamma-secretase inhibitors for potential use in Alzheimer's disease have been designed that incorporate a substituted hydrocinnamide C-3 side chain. A syn combination of alpha-alkyl or aryl and beta-hydroxy or hydroxymethyl substituents was shown to give highly potent compounds. In particular, (2S,3R)-3-(3,4-difluorophenyl)-2-(4-fluorophenyl)-4-hydroxy-N-((3S)-2-oxo-5-phenyl-2,3-dihydro-1H-benzo[e][1,4]diazepin-3-yl)butyramide (34) demonstrated excellent in vitro potency (IC(50) = 0.06 nM). 34 could also be selectively methylated to give [(3)H]-28, which is of use in radioligand binding assays.

Suzuki cross-coupling mediated by tetradentate N-heterocyclic carbene (NHC)-palladium complexes in an environmentally benign solvent

A highly effective, easy to handle and environmentally benign process for palladium mediated Suzuki cross-coupling was developed. By utilizing a solid support based NHC-palladium catalyst, cross couplings of aryl bromides with phenylboronic acid were achieved in neat water under air. A high ratio of substrate to catalyst was also realized.

Quantitative formation of [2]catenanes using copper(I) and palladium(II) as templating and assembling centers: the entwining route and the threading approach

Transition metal-mediated templating and self-assembly have shown powerful potentials for the synthesis of interlocked molecules. These two strategies were combined in designing and preparing a new type of coordination catenanes incorporating Cu(I) and Pd(II) metal centers. The ligand designed here contains a phenanthroline core and pyridine sidearms (compound 1). Using this phenanthroline-pyridine conjugated ligand, two approaches were examined, which were shown to be surprisingly efficient for the catenane synthesis: the entwining route (entwining of two ligands around Cu(I) followed by Pd(II) clipping) and the threading approach (Cu(I)-templated threading of a cyclic ligand on an acyclic ligand followed by the Pd(II) clipping of the second ring). In the former method, stepwise treatment of 1 with Cu(CH(3)CN)(4)PF(6) (templating center) and enPd(NO(3))(2) (assembling center) gives rise to the quantitative formation of CuPd(2) catenane 18. In the latter method, Cu(I) templates the threading of phenanthroline-containing macrocycle 2 on ligand 1, which is followed by Pd(II) clipping to give hetero catenane 20. In both approaches, the formation of catenanes is convincing thanks to the strong templating effect of Cu(I), while the ring closure steps are efficiently furnished by Pd(II)-directed self-assembly.

Host-[2]rotaxane: advantage of converging functional groups for guest recognition

A host-[2]rotaxane was constructed by converting a diaminophenylcalix[4]arene into a [2]rotaxane using the DCC-rotaxane method (Zehnder, D.; Smithrud, D. B. Org. Lett. 2001, 16, 2485-2486). N-Ac-Arg groups were attached to the dibenzo-24-crown-8 ring of the rotaxane to provide a convergent functional group. To demonstrate the advantage provided by the rotaxane architecture for recognition of guests that contain a variety of functional groups, association constants (K(A)) for N-Ac-Trp, indole, N-Ac-Gly, fluorescein, 1-(dimethylamino)-5-naphthalenesulfonate, and pyrene bound to the [2]rotaxane were determined by performing (1)H NMR and fluorescence spectroscopic experiments. The host-[2]rotaxane had the highest affinity for fluorescein with a K(A) = 4.6 x 10(6) M(-)(1) in a 98/2 buffer (1 mM phosphate, pH 7)/DMSO solution. A comparison of K(A) values demonstrates that both the aromatic pocket and ring of the host-[2]rotaxane contribute binding free energy for complexation. Association constants were also derived for the same guests bound to the diaminophenylcalix[4]arene and to a diphenylcalix[4]arene that contained arginine residues displayed in a nonconvergent fashion. The host-[2]rotaxane provides higher affinity and specificity for most guests than the host with divergent N-Ac-Arg groups of the one that only has an aromatic pocket. For example, the K(A) for the complex of the host-[2]rotaxane and fluorescein in the DMSO/water mixture is more than 2 orders of magnitude greater than association constants derived for the other hosts.

Synthesis and pharmacological evaluation of substituted naphth[1,2,3-de]isoquinolines (dinapsoline analogues) as D1 and D2 dopamine receptor ligands

Dinapsoline ((2); (+/-)-dihydroxy-2,3,7,11b-tetrahydro-1H-naphth[1,2,3-de]isoquinoline) is a full D(1) dopamine agonist that also has significant D(2) receptor affinity. Based on a similar pharmacophore, dinapsoline has pharmacological similarities to dihydrexidine ((1); (+/-)-trans-10,11-dihydroxy-5,6,6a,7,8,12b-hexahydrobenzo[a]phenanthridine), the first high affinity full D(1) agonist. Small alkyl substitutions on the dihydrexidine backbone are known to alter markedly the D(1):D(2) selectivity of dihydrexidine, and it was of interest to determine whether similar SAR exists within the dinapsoline series. This report describes the synthesis and pharmacological evaluation of six analogues of dinapsoline: N-allyl-(3);N-n-propyl- (4); 6-methyl- (5); 4-methyl- (6); 4-methyl-N-allyl- (7); and 4-methyl-N-n-propyl-dinapsoline (8). As expected from earlier studies with the dihydrexidine backbone, N-allyl (3) or N-n-propyl (4) analogues had markedly decreased D(1) affinity. Unexpectedly, and unlike the dihydrexidine series, these same substituents did not markedly increase D(2) affinity. The addition of a methyl group to position 6 (5) increased D(1):D(2) selectivity, but less markedly than did the analogous 2-methyl substituent added to 1. Unlike the analogous 4-methyl substituent of 1, the addition of a 4-methyl-group (6) actually decreased D(1) affinity without affecting D(2) affinity. These data demonstrate that the dinapsoline (2) backbone can be modified to produce dopamine agonists with novel properties. Moreover, as rigid ligands in which small substituents can cause significant changes in selectivity, they are important tools for deriving 'differential' SARs of the dopamine receptor isoforms.

Isomer specific synthesis using the Suzuki-coupling. Polychlorinated terphenyls as standards for environmental analysis

Defined polychlorinated terphenyl (PCT) single congeners as reference standards are the prerequisite for the development of analytical methods for their determination and quantification in the environment. The selective synthesis of PCTs for environmental analytical purposes by application of the Suzuki-coupling reaction is described. Under easily modified standard reaction conditions of this coupling process the PCTs can be obtained by reaction of benzeneboronic acids with dibromobenzenes mostly in good yields, as described by the synthesis of following PCT congeners: p-PCT (3,3("),5,5(")-tetrachloro-, 2,2("),4,4(")-tetrachloro-, 2('),3,3("),5,5(")-pentachloro-); m-PCT (3,3("),5,5(")-tetrachloro-) and o-PCT (3,3("),5,5(")-tetrachloro-). The terphenyl congeners were characterized by NMR (1H, 13C)- and FT-IR-spectroscopy. Their purity was checked by GC/MS analysis. The experimental and quantum-chemically calculated FT-IR-spectra were compared and it was shown, that the determination of the chlorine substitution pattern in the terphenyl congeners by their typical absorption spectra is possible.

Chlorosulfonyl isocyanate reactions with N-(alkoxycarbonyl)-2-azabicyclo[2.2.0]hex-5-enes. Regiospecific two-atom insertion pathways

Addition of the uniparticulate electrophile chlorosulfonyl isocyanate to the nitrogen atom of N-(alkoxycarbonyl)-2-azabicyclo[2.2.0]hex-5-enes 1 is followed by ring cleavage and recombination. The parent 4-methyl, 5-methyl, 5-bromo, and 5-phenyl azabicycles 1a-f afforded novel 2,4-diaza-3-oxo-bicyclo[4.2.0]oct-7-enes 10a-f. The 3-endo-phenyl azabicycle 1g rearranged to a 6-styryl-1,3-diaza-2-oxo-cyclohex-4-ene 12.

Modular approach to novel chiral aryl-ferrocenyl phosphines by Suzuki cross-coupling

Two novel planar chiral and atropisomeric P,N and P,O aryl-ferrocenyl ligand systems have been developed. The strategy is short and involves a new synthetic approach to aryl-ferrocenyl compounds via a Suzuki cross-coupling procedure. The modular design can easily give access to variety of chiral mono- and bidentate ligands. Two simple derivatives of a novel chiral bidenate P,N ligand belonging to the MOPF family have been synthesized and tested in the enantioselective copper-catalyzed addition of diethyl zinc to an enone and a "difficult" diester. Moderate to excellent yields and enantioselectivities up to 58% were obtained using 1 mol % Cu(OTf)(2) and 1.5 mol % chiral ligand.

2,3-Diarylbenzopyran derivatives as a novel class of selective cyclooxygenase-2 inhibitors

A new series of cyclooxygenase-2(COX-2) inhibitors with naturally occurring flavone as the main skeleton has been synthesized and their biological activities were evaluated for cyclooxygenase inhibitory activity. Rational structural modifications were applied to potent COX-2 inhibitors to obtain the desired pharmacokinetic profiles for improved oral anti-inflammatory activity.

Clinical implementation of 4-dihydroxyborylphenylalanine synthesised by an asymmetric pathway

Boron neutron capture therapy (BNCT) is an experimental therapeutic modality combining a boron pharmaceutical with neutron irradiation. 4-Dihydroxyborylphenylalanine (L-BPA) synthesised via the asymmetric pathway by Malan and Morin [Synlett. 167-168 (1996)] was developed to be the boron containing pharmaceutical in the first series of Finnish BNCT clinical trials. The final product was >98.5% chemically pure L-BPA with L-phenylalanine and L-tyrosine as the residual impurities. The solubility of L-BPA was enhanced by complex formation with fructose (BPA-F). The pH and osmolarity of the BPA-F preparation is in the physiological range. Careful attention was given to the pharmaceutical quality of the BPA-F preparations. Prior to starting clinical trials the acute toxicity of L-BPA was studied in male albino Sprague-Dawley rats. In accordance with earlier studies no adverse effects were observed. After completion of the development work L-BPA solution was administered to brain tumour patients in conjunction with clinical studies for development and testing of BPA-based BNCT. No clinically significant adverse events attributable to the L-BPA i.v. infusions were observed. We conclude that our synthesis development, complementary preclinical and clinical observations justify the safe use of L-BPA up to clinical phase III studies with L-BPA produced by the asymmetric pathway, originally presented by Malan and Morin in 1996.

Synthesis and deprotonation of 2-(pyridyl)phenols and 2-(pyridyl)anilines

2-(2- and 3-Pyridyl)anilines (1, 2), 2,2-dimethyl-N-[2-(2- and 3-pyridyl)phenyl]propanamides (3, 4), and 2-, 3- and 4-(2-methoxyphenyl)pyridines (7-9) are readily synthesized using cross-coupling reactions. Whereas the amines 1, 2 undergo side reactions, the corresponding amides 3, 4 are deprotonated with lithium 2,2,6,6-tetramethylpiperidide (LTMP): the compound 3 at C6' under in situ quenching, and the compound 4 at C4'. When the ether 7 is subjected to the same reagent, lithiation occurs at C6'.