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Naphthothiophenes were prepared from commercially available 2,3-dibromothiophenes in two steps by one-pot Suzuki/Sonogashira or Sonogashira/Suzuki coupling reactions, followed by intramolecular alkyne-carbonyl-metathesis reactions. The final cyclization reaction proceeds in the presence of p -toluenesulfonic acid and provides a rapid access to two series of isomeric naphthothiophenes.

Various N-fused isoquinoline derivatives were synthesized using a new one-pot reaction of 1-bromo-2-(2,2-difluorovinyl)benzenes with N-H group containing heterocycles followed by intramolecular palladium-catalyzed C-H arylation. The method described gives convenient access to diverse structures of N-fused polycyclic isoquinolines. Sixteen of the synthesized compounds were screened as potential human nucleotide pyrophosphatase/phosphodiesterase 1 and 3 (h-NPP-1 and h-NPP-3) inhibitors. The most effective h-NPP-1 inhibitor showed an IC 50 value as high as 0.36 ± 0.06 μM, whereas the most potent h-NPP-3 inhibitor posessed an inhibitory value of 0.48 ± 0.01 μM. Kinetic and molecular docking studies of both most effective inhibitors were carried out.

The cyclization of 2,3-dihalopyridines with readily available imines provides a convenient and regioselective approach to 4- and 7-azaindoles. The regioselectivity can be controlled by the choice of the halogen atoms at the pyridine ring (chlorine versus bromine).

A new and convenient method for the synthesis of indolo[1,2-f]phenanthridines via palladium-catalyzed domino C-N coupling/hydroamination/C-H arylation reactions was developed. The reactions allow for the synthesis of various phenanthridines in good yields from easily accessible starting materials using a single palladium catalyst.

Two concise and efficient approaches were developed for the synthesis of α- and δ-carboline derivatives. The success of the synthesis relies on site-selective Suzuki-Miyaura reactions of 1-chloro-2-bromopyridine or 2,3-dibromopyridine with 2-bromophenylboronic acid and subsequent cyclization with amines which proceeds by twofold Pd-catalyzed C-N coupling reactions.

A new and efficient strategy for the synthesis of 3,9'- and 2,9'-biscarbazoles was developed. Our strategy relies on the cyclization of 1,1'-biphenyl-2,2'-diyl bis(trifluoromethanesulfonate) with 4- or 3-anisidine, transformation of the methoxy to a triflate group and subsequent oxidative Pd-catalyzed cyclization with various anilines.

The authors of this work have optimized a novel synthetic route towards glucose‐based PdII‐bis(NHC) complexes in only 4 steps with total yields up to 73 %. The synthesis route encompasses an Appel reaction towards 6‐iodo‐glucopyranosides, followed by acyl‐protection, then quaternization with imidazoles and finally the conversion of these acyl‐protected glucosyl imidazolium salts to their respective palladium(II)bis(NHC) complexes, via an intermediary silver(I) complex. Overall, 11 acyl‐protected glucosyl imidazolium iodides as NHC‐precursors and 15 complexes have been synthesized. The structure‐activity relationships of different functionalizations in these complexes and their reactivity in a model Suzuki‐Miyaura between bromobenzene and 4‐tolueneboronic acid reaction has been investigated, and a highly reactive complex leading to >99 % yield at 0.005 mol% catalytic loading has been found. [ABSTRACT FROM AUTHOR]

Four different isomeric azadibenzo[a,e]pyrenes (benzo[4,10]anthra[9,1‐gh]isoquinolines and benzo[4,10]anthra[1,9‐fg]isoquinolines) were prepared by combination of Pd‐catalyzed Sonogashira and Suzuki cross‐coupling, Brønsted acid mediated cycloisomerization and Pd‐catalysed CH‐activation reactions. The optical properties have been studied by steady‐state absorption and emission spectroscopy in different solvents and during acid titration. Trifluoroacetic acid protonation strongly affects absorption and emission properties, with variations depending on the position of the nitrogen atom of the specific compound. Electrochemical analysis showed distinct oxidation and reduction potentials. DFT calculations provided further insights into electronic properties. [ABSTRACT FROM AUTHOR]

A series of N‐doped Benzo[b]fluoranthenes was synthesized. Specifically varying the position of the Nitrogen atom in all four positions of the bottom ring. In the last reaction step the five‐membered ring of the unsubstituted core structure is formed by palladium catalyzed CH‐activation. This synthetic approach allows for the selective introduction of heteroatoms into the core structure and leads to four regioisomeric products. Subsequently the optical and electrochemical properties of these polyaromatic heterocycles were compared. DFT/TD‐DFT and NICS calculations were performed to further analyze, how the position of Nitrogen impacts the overall characteristics of the molecules. This composes a thorough study on the chemical behavior of N‐doped Benzo[b]fluoranthenes. [ABSTRACT FROM AUTHOR]

A series of hitherto unknown 5,14‐diphenylbenzo[j]naphtho[2,1,8‐def][2,7]phenanthrolines, containing a 5‐azatetracene and a 2‐azapyrene subunit, were prepared by combination of Pd‐catalyzed cross‐coupling reactions with a one‐pot Povarov/cycloisomerization reaction. In the final key step four new bonds are formed in one step. The synthetic approach allows for a high degree of diversification of the heterocyclic core structure. The optical and electrochemical properties were studied experimentally and by DFT/TD‐DFT and NICS calculations. Due to the presence of the 2‐azapyrene subunit, the typical electronic nature and characteristics of the 5‐azatetracene moiety are lost and the compounds are electronically and optically more related to 2‐azapyrenes. [ABSTRACT FROM AUTHOR]

Spirocyclic diindenothiophenes were prepared by cyclization of tosylhydrazones, readily available from ketones, with 3,4-dibromo-2,5-bis(2-bromphenyl)thiophene. For bicyclic ketones, the bis-spirocycles were formed with very good diastereoselectivity. [ABSTRACT FROM AUTHOR]

A convenient three‐step synthesis of dibenzo[a,j]acridines is reported which relies on regioselective Pd‐catalyzed cross‐coupling reactions of 2,3,5,6‐tetrachloropyridine and subsequent Brønsted acid mediated cycloisomerization. Products are obtained in good yields and the method is broadly applicable. For selected dibenzo[a,j]acridines, photophysical and electrochemical properties were studied. [ABSTRACT FROM AUTHOR]

A variety of thienoquinolones were synthesized from readily accessible thiophene derivatives by regioselective acylations and subsequent two‐fold Buchwald–Hartwig–amination. This cyclization allows a convenient synthesis of biologically and pharmaceutically important thienoquinolones. Several thienoquinolones were synthesized in good to very good yields. The optical properties of the products were studied in detail. [ABSTRACT FROM AUTHOR]

A convenient synthesis of various benzoacridines and benzophenanthridines from readily available dihalogenated quinolines is reported. The synthesis is based on regioselective Suzuki and Sonogashira reactions followed by Brønsted acid‐mediated cycloisomerization. The developed methodology is highly modular and allows the construction of various ring systems and substitution patterns in high yields. The optical and electrochemical properties of selected derivatives were investigated. [ABSTRACT FROM AUTHOR]

A straightforward, site-selective arylation of the bis(triflate) of estrone by Suzuki–Miyaura reactions has been developed. Monoarylation occurs selectively at the D-ring with good to excellent yield. Such products were exemplarily employed for the synthesis of estrones containing two different aryl substituents. [ABSTRACT FROM AUTHOR]

4-Bromo-2,3,5-trichloro-6-iodopyridine has been synthesized for the first time and applied in chemo- and site-selective Suzuki-Miyaura cross-coupling reactions. This novel start- ing material allows the selective synthesis of pentaarylpyridines with up to four different aryl substituents. [ABSTRACT FROM AUTHOR]

A new and efficient two-step procedure for the preparation of 5,7-disubstituted 5,7-dihydropyrido[2,3- b:6,5- b′]diindoles, containing aryl-, benzyl- as well as alkyl-substituents has been developed. This methodology consists of a chemo-selective double Suzuki-Miyaura cross-coupling reaction followed by a fourfold Buchwald-Hartwig amination reaction. UV/VIS absorption and fluorescence measurements have been carried out for a selected series of compounds. The results are summarized and compared with those of the isomeric 5,7-disubstituted 5-7-dihydropyrido[3,2- b:5,6- b′]diindoles. [ABSTRACT FROM AUTHOR]

Polyalkynylated naphthalenes were obtained from easily available 2,3-dibromobenzoquinone. The developed methodology consists of a substitution of both carbonyl groups of the quinone moiety by lithium acetylide followed by a Pd-catalyzed cross-coupling reaction. Optical properties of selected compounds were studied. [ABSTRACT FROM AUTHOR]

Two new and efficient routes to benzothieno[2′,3′:4,5]pyrrolo[1,2- f]phenanthridines have been developed. Alkynylated benzothiophenes reacted with various anilines to the target compounds in a domino reaction consisting of a C−N coupling-, hydroamination- followed by a final, ring-closing C−H arylation step. Products were isolated in moderate to good yields. [ABSTRACT FROM AUTHOR]

A range of aza-ullazines, which represent a new heterocyclic core structure, were synthesized through a scalable four-step reaction, including a Sonogashira reaction and metal-free cyclization promoted by p-toluenesulfonic acid. The optical and electrochemical properties of selected derivatives were investigated, they were found to have similar absorption and emission spectra but a higher oxidation potential than the parent ullazine core. [ABSTRACT FROM AUTHOR]

1,4-Diaryl-9H-fluoren-9-ones were prepared by regioselective Suzuki-Miyaura cross-coupling reaction of the bis(triflate) of 1,4-dihydroxy-9H-fluoren-9-one. The reactions proceeded with excellent site selectivity. The first attack occurs at position 1, due to electronic reasons. [ABSTRACT FROM AUTHOR]

8-Aryl- and 6,8-diarylflavones were prepared by Suzuki- Miyaura reactions of 6,8-dibromoflavone. In spite of the greater steric hindrance, the first attack proceeded with good site selectivity at position 8. [ABSTRACT FROM AUTHOR]

Arylated isoflavones are prepared by Suzuki-Miyaura crosscoupling reactions of the bis(triflate) of 4',7-dihydroxyisoflavone. The reactions proceed with very good regioselectivity in favor of the electronically more deficient position. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed one-pot reaction for the synthesis of benzo[b]carbazolediones is described which proceeds by amination of 2,3-dibromonaphthoquinone, Suzuki cross-coupling with (2-bromophenyl) boronic acid, and subsequent intramolecular C-N Buchwald- Hartwig cyclization with amines. [ABSTRACT FROM AUTHOR]

Sonogashira reactions of steroids have been studied. The reaction of a-estron-16-methylidenyloxy triflate with various alkynes afforded novel alkynylvinylidene steroids. The reactions proceeded in good to quantitative yields, with excellent E-selectivity and with a broad synthetic scope. [ABSTRACT FROM AUTHOR]

We report Pd- and Ni-catalysed, guided and regioselective CH arylations of a series of fused 3-nitropyridines. The method described here is a facile tool for the chemical functionalisation of drug-like fused pyridines. The scope and limitations of the reaction, the chemical potential of the nitro group and a putative reaction mechanism are discussed. [ABSTRACT FROM AUTHOR]

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Arylated naphthalenes were prepared by Suzuki-Miyaura reactions of the bis(triflate) of methyl 3,7-dihydroxy-2-naphthoate. The reactions proceeded with very good site-selectivity in favor of the sterically less hindered position 7, despite the proximity of position 3 to the electron-withdrawing ester group which plays a decisive role for the site-selectivity of Suzuki-Miyaura reactions of related substrates. [ABSTRACT FROM AUTHOR]

Mono-, di-, and tetraalkynylated selenophenes were prepared by site-selective Sonogashira reactions of tetrabromoselenophene. Aryl-, alkyl-, and trimethylsilylacetylenes were suitable substrates for this procedure. The first attack occurred regioselectively at C-2 and C-5. In addition, differently diarylated dialkynylselenophenes were prepared using site-selective Suzuki and Sonogashira reactions. [ABSTRACT FROM AUTHOR]

A new strategy for the synthesis of polycyclic imidazole-containing N-heterocycles, based on the two general synthetic ways, namely the Pd(II)-catalyzed intramolecular arylation via CH/CHal and CH/CH coupling reactions, was developed. The method proposed here enables the synthesis of many fused N-heterocycles containing purine, 1-deazapurines and benzimidazole structural units. [ABSTRACT FROM AUTHOR]

A variety of mono- and diarylated naphthyridine derivatives were prepared by site-selective Suzuki-Miyaura cross-coupling reactions of 5,7-dichloro-1,6-naphthyridine. The first attack occurs at position 5. [ABSTRACT FROM AUTHOR]

A variety of mono- and diarylated quinoxaline derivatives were prepared by site-selective Suzuki-Miyaura crosscoupling reactions of 2,6-dichloroquinoxaline. The selectivity is controlled by electronic parameters. [ABSTRACT FROM AUTHOR]

Described is the synthesis of novel arylated and alkynylated 2,4′-diphenyl sulfones based on what are, to the best of our knowledge, the first palladium(0)-catalyzed cross-coupling reactions of bis(triflates) of 2,4′-bis(hydroxy)diphenyl sulfone. The reactions proceed with very good site-selectivity. [ABSTRACT FROM AUTHOR]

Palladium(0)-catalyzed Suzuki and Sonogashira crosscoupling reactions of the bis(triflates) of 2,4- and 3,4-dihydroxybenzophenone afforded 2,4- and 3,4-diarylbenzophenones, respectively. The reactions proceeded with very good site-selectivity in favor of position 4. [ABSTRACT FROM AUTHOR]

5,10-Diaryl-11H-benzo[b]fluoren-11-ones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 5,10-dihydroxy-11H-benzo[b]fluoren-11-one. The reactions proceed with excellent site-selectivity. The first attack occurs at position 10, due to electronic reasons. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of N-protected tribromopyrazoles are reported. Their reaction with three, two, or one equivalents of arylboronic acids afforded 3,4,5-triarylpyrazoles, 3,5-diaryl-4-bromopyrazoles, or 5-aryl-3,4-dibromopyrazoles, respectively. All reactions proceeded with very good site-selectivity. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of pentachloropyridine are reported. The reaction with two equivalents of arylboronic acids gave 2,6-diaryl-3,4,5-trichloropyridines, while the reaction with one equivalent of arylboronic acid afforded 2-aryl-3,4,5,6-tetrachloropyridines. The one-pot reaction of pentachloropyridine with two different arylboronic acids resulted in the formation of 2,6-diaryl-3,4,5-trichloropyridines containing two different aryl groups. All reactions proceeded with very good site selectivity. [ABSTRACT FROM AUTHOR]

1,2-Diarylanthraquinones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 1,2-dihydroxyanthraquin�one (alizarin). The reactions proceed with excellent site selectivity. The first attack occurs at the sterically more hindered position 1, due to electronic reasons. [ABSTRACT FROM AUTHOR]

The first Suzuki-Miyaura reactions of 2,3,5-tribromothiophene are reported. These reactions provide a convenient and site-selective approach to 5-aryl-2,3-dibromothiophenes, 2,5-diaryl-3-bromothiophenes, and 2,3,5-triarylthiophenes. [ABSTRACT FROM AUTHOR]

N-Methyl-2,3,4,5-tetrabromopyrrole is transformed into a variety of alkynyl-substituted pyrroles by regioselective Sonogashira cross-coupling reactions. In this context, the synthesis of the first tri- and tetra(1-alkynyl)pyrroles is reported. [ABSTRACT FROM AUTHOR]

3-Aryl-2-nitroindoles were prepared via CH-activation reactions of N-methyl-2-nitroindole. [ABSTRACT FROM AUTHOR]

7,8-Diarylflavones were prepared by Suzuki-Miyaura reactions of the bis(triflate) of 7,8-dihydroxyflavone. The first attack proceeded with very good site selectivity at position 7, due to steric and electronic reasons. [ABSTRACT FROM AUTHOR]

Functionalized anthraquinones were prepared by domino ‘twofold Heck-6π-electrocyclization’ reactions of 2,3-dibromo�naphthoquinone. [ABSTRACT FROM AUTHOR]

The palladium(0)-catalyzed Suzuki cross-coupling reaction of the bis(triflates) of methyl 2,5-dihydroxybenzoate afforded p-terphenyls. The reactions proceeded with very good site selectivity. The first attack occurred at carbon atom C-5. [ABSTRACT FROM AUTHOR]

and heterocyclic benzoin derivatives were prepared by Sonogashira coupling of alkynes with 1,2-dihaloalkenes and subsequent oxidation of the alkyne to a 1,2-diketone. The Pd-catalyzed reaction of the product with (2-bromophenyl)boronic acid in the presence of phenylacetylene resulted in formation of cyclic benzoin derivatives by Suzuki-Miyaura reaction and subsequent Pd catalyzed nucleophilic addition to the carbonyl group. Hitherto unprecedented 5-hydroxy-5-phenylbenzo[ b ]naphtho[1,2- d ]thiophene-6(5H)-ones and their regioisomers were prepared from 2,3-dibromobenzothiophene. Phenanthrene benzoin derivatives were prepared from 2-bromo-1-iodobenzene. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of new ethynylated benzoindoles were synthesized starting with the nucleophilic attack of naphthoquinone by lithium acetylides. The resulting 1,4-diethynylnaphthalenes were applied in palladium catalyzed CN coupling - hydroamination domino reactions. The obtained compounds fluoresce in the near ultraviolet and blue spectral region with high quantum yields (65–78%). [ABSTRACT FROM AUTHOR]

Abstract: Chemoselective Suzuki–Miyaura reactions of 2-bromo-1-(trifluoromethanesulfonyloxy)naphthalene, 1-bromo-2-(trifluoromethanesulfonyloxy) naphthalene and 2-acetyl-4-bromo-1-(trifluoromethanesulfonyloxy)naphthalene, which are all readily available from the corresponding tetralone derivatives, afforded a variety of mono- and diarylnaphthalenes. The reactions generally proceed with excellent chemoselectivity in favour of the bromide position, no matter whether the bromide is located at position 1 or 2 of the naphthalene or whether the carbon attached to the triflate group is electronically more deficient by the presence of a neighbouring acetyl group. [Copyright &y& Elsevier]

Abstract: The palladium(0)-catalyzed Suzuki cross-coupling reactions of the bis(triflates) of 1,3- and 1,4-dihydroxythioxanthone afforded various aryl-substituted thioxanthones. While the Suzuki reactions of the bis(triflate) derived from 1,3-dihydroxythioxanthone proceeded by site-selective attack in favor of position 3, the reactions of the bis(triflate) of 1,4-dihydroxythioxanthone proceeded in favor of position 1. The site-selectivity is controlled by steric and electronic parameters. [Copyright &y& Elsevier]

Abstract: The first Suzuki–Miyaura reactions of 2,3,5-tribromo-N-methylpyrrole are reported. These reactions proceed with very good site-selectivity in favour of position 5 which is more reactive than position 2, due to steric reasons. The second attack occurs at position 2 which is more electron deficient than position 3. [Copyright &y& Elsevier]

Abstract: Fluoranthenes were prepared by domino two-fold Heck/electrocyclization/dehydrogenation reactions of 1,2-dibromoacenaphthylene. [Copyright &y& Elsevier]